All suits of armor are made for humans. The other races have extreme clipping problems that breaks immersion.
I like transmogging and humans are the perfect race for it.
Plus Alliance are the good guys ( in our world, Alliance would be the doctors and nurses who saves lives, horde would be the conspiracy theorist anti-vaxxers )
As a rule, living things do not like change. As a rule all things change.
The purpose of organizations is usually to resist or control change. Both are futile.
A few individuals and organizations seek to force change and they fail because they think understand change.
Horde or Alliance are simply āstylesā of resisting change and it comes down to how you want to look being on the wrong side of entropy.
Omnes fines.
I hate ALL factions in any game and/or real life.
In particular, I hate the two trainwrecks that Alliance and Horde are.
But hate Horde more, because Horde wants to be HAR HAR ME SMASH and at the same time cry āBad Allies donāt see how nice and good we are. Bad Allies! Bad!ā
And Shreds, what a bummer.
That was the long reason I hate the Horde.
The short reason is the āPath of Gloryā.
Absolutely perfect! 
As a lover of classic (i.e. heavy metal) music, I confirm that āmetalā is a completely different vibe. Maldraxxus has a metal vibe, the reason I find it exhilarating sometimesā¦
Back when TBC was announced, and they basically said āWe know youāve been asking for playable Blood Elves since before the game was launched, so here they areā¦ but on Horde!!ā everyone was basically all āWhat? Doesnāt make much sense, but, I guess theyāre putting them on Horde because the Horde needs a āpretty raceā, right?ā And weāve even seen several comments made by ex-Blizzard employees that have backed that up, saying things like āWe polled players in Asia, and they said they wished there were pretty characters on Horde so their girlfriends would play Horde.ā
Regardless of if thatās the full truth, though, it has stuck with many players. Not only that but even though Blood Elves started off with some story beats that tried to make them less awkward on the Horde, even those have been removed and theyāre just āAlliance, but on the Horde.ā I mean, lets face it: If Blood Elves were removed from the game, the Horde story itself wouldnāt even change.
Does anyone else struggle to understand why people like the opposite faction?
no, because Iām an adult and am more than capable of grasping the concept that different people like different things, and a silly video game faction isnāt part of someoneās identity.
You can make anything a part of your identity. Most people with tattoos believe that their ink is part of their identity. I have Horde ink. So there we are.
Identity is elusive and illusory. Who we are depends primarily upon who we choose to be, and the influences relevant to our identities are generally the ones we have hand-picked, no matter if other people consider them valid or not. 
I simply donāt like horde Aesthetics. Not just the races but the structures.
Same reason I didnāt really care for Pandaria
Iāve felt that way about Horde since Cataclysm. I still level my Horde alts, but I really have to drag them through it.
Leveling my poor tauren shaman in BfA was particularly rough. That dude was created during late Vanilla or early TBC under Thrallās Horde, so every time little miss elfpants shows up itās like nails on a chalkboard to him. Just blegh, and the brief reprieves given by Zandalar questing were just barely enough to make it palatable. At BfA cap where all the questing centers around Sylvanas and her mustache-pet itās just a hard no.
Alliance might be āboringā but Iāll take that over being straight up baddies but not willing to admit it.
I played Alliance from 2004 until 2009. I played Blood Elves as soon as they were released, but my Main was my NE Hunter.
Something yuck happened, and I transferred all my characters to Horde. I honestly felt as though Iād come home. I always adored World PvP, and found the Faction divide fun.
Then Blizz Devs put us through the 'awful-stereotyping-youāre-now-the-bad-guys crap, and after the BfA pre-expac event the Factions just felt terrible to me.
Why savagely divide the playerbase, and then inject such hatred and bitterness. The World has enough ugliness. It all just felt horrible.
I Main Horde, and love the Horde Faction so much, but I also play Alliance, and donāt hate the Alliance at all.
Ultimately I think most people on my servers are really nice, regardless of their Faction, and I canāt wait until we are more united, and, eventually, hopefully, the Factions are dissolved to some extent.
So no, I donāt dislike the opposite Faction. 
No. My struggle is to understand why anyone would pay this much to only play half of the game. I donāt understand people who donāt have toons in both factions, and vilify those who do. Thatās my struggle.
Everyone thinks theyre the good guy even when theyre doing wrong. Especially when it comes to WoW
This is pretty funny coming from a Blood Elf.
You realize that the leader of the Blood Elves also crown themselves as a King? Lorāthemar is a temp.
You are literally playing the humans of the Horde.
No because Iām an empath.
I like both factions, but Iāve had much worse experiences with horde communities/servers/players. Plus I donāt like orange and thatās a common trend with horde cities.
The lore is something questionable all on its own, but between Sylvanas and Garrosh, it feels kind of bad. I did really love Volājin and I think the new council could be decent. Lorāthemar seems sort of douchey sometimes, but heās had some great moments. Thalyssra basically took massive offense to Tyrande asking if sheād be the next Elisande and then seemed happy for watching Alleria and her people being ejected/threatened with capture. I LOVED Thalyssra, but this seems like a massive oversight in her personality after both factions helped out in Suramar. Poor Baine is justā¦ there. Of course they also get another ābad guyā leader in Gallywix. Iām torn on Talanji. She changed drastically.
Tyrande and Jaina were both given ācrazyā phases like Sylvanas. Haha woman bad /s. Genn feels dumbed down =[ and Malfurion is useless 90% of the time in game. Mekkatorque always gets forgotten. Velen gets decent spotlight sometimes, like in Legion. That was great! But overall kind of sad. I donāt know what to think of Magni anymore. Turalyon is going to be a nutcase imo. Anduin gives me hope, surprisingly.
So uhā¦ yeah, both sides are questionable. Crossing my fingers for better narrative design in game.
I donāt have any strong bias, but common trends make already bad feelings worse. Especially when it comes to the community. I am, however, very excited to play my nightborne and moose with my friends when cross faction comes around.
for me I cant undestand how any normal, sane , and decent Human being could play (Thats play as in do endgame stuff regularly, not just level) any evil race/faction at all ( and yes horde are evil) . To me that shows a deep flaw in their personality that will manifest in normal human society.
Even just leveling horde a good proportion of the quests are sickening
Funnily enough I started as a Human back in Vanilla. A friend was letting me play at the time, I got to 60 before himā¦was a good time. Then we had a falling out and he decided to just delete my toon (which was ready for Ahnāqiraj), went out that night and bought the game myself, made an undead on the same server with the same name as the one that got deleted. I leveled it to 60 and then smashed him multiple times once I found him out in the world.
My hate for the Alliance started there, and was compounded from all of the ganks I received in Hillsbradā¦ that hate wore off after a long while though. While I canāt really love the other faction, I do have friends that rolled over there, so At least I can actually play with them now.
I know. I hate blood elves.
Iām playing one because Blizzard doesnāt give me any choice. If I want to be a Demon Hunter (and I do), I have to be a human of the Horde.
Believe me, Iād have chosen any other Horde race over this one if they had allowed me to do so.
lol.
Well, Iāll take this as you making an argument in good faith that represents your actual opinion. I find it insane and absurd, but you find me insane and absurd, so it all checks out.
From my perspective, thereās no such thing as good or evil. There are only different sides, each looking out for their own best interests. I hate the Alliance for the same reason I hate militaries and law enforcement organizations. I donāt respect so-called authority, and I believe in radical individualism and unbridled freedom.
I donāt support anyone āfollowing the leader,ā be they Horde or Alliance. Iām an anarchist above all else. I feel that the Hordeās heirarchy is less formal and more easily defied/avoided. Rogue operatives who do their own thing but still represent the Horde is the ideal for me.
On the off chance that you play or have played Dungeons & Dragons, my alignment is Chaotic Neutral, and I donāt know how to play anything else, because no other alignment makes any sense to me at all.