This, like all addons need to be looked at as a good thing that allows the dev team to make the game better.
DBM does make fights easier, but in turn that forces the dev team to make the game harder and with more mechanics. Simply having the addon means only half the fight, you still need to understand the mechanics in order to best utilise the addon and be good at the fight.
TSM and other AH addons make AH workings easier, therefore it forces them to change the 15 year old AH.
Damage meters are great in that they allow you to see who on your team is under performing, because otherwise there would need to be no mana, no time limit and no punishing mechanics. If they left it as is and removed the DPS meters you would not be able to help your groups and not be able to progress, you would have no idea who is falling behind and needing help.
Raider is in the same boat as DPS meters, if you had no idea what someone was going to bring than you would simply not pug and only run with friends. In no way are the top players going to pug some random they have no stats or idea about, hence the need for addons to exist. Do you truly believe no IO would make the game better?
No, no addons means you will not be as good as other players because thanks to addons the game has evolved, the game allows us to help each other, recruit the right person, progress the right we want to. I know one person who has no addons and is up to scratch with mythic raiding and anything under an M15, one.
Everyone else who admits to not having addons is almost always worse than everyone else I play with, and not just a bit, I am talking half the DPS and constantly getting caught out by mechanics, the same mechanics you want us to familiarise ourselves with without the use of addons.
You see OP, you are the epitome of “IO is bad for pugs and addons should be banned” when your highest IO in BfA on this character is less than 500. I ran my characters, 4 of them, from the ground up multiple times across BfA, 3 of which have gotten above 1K with no carries, 2 of which in S3 are around 1.3K.
No doubt you also don’t run addons, find it hard to keep up with all the information and struggle to keep on top of the tough mythic level mechanics.
You know what is better than complaining about things that make the game better? Admitting your own limits, admitting to yourself and saying “This is the best I can be” and accepting that.
I run M15 or lower, I run around 4-5 mythic raid bosses and am happy with that, I may never get good enough to kill all mythic raid bosses, I may never be good enough to time an M16 or higher, maybe one day, but based on how I am after 15 years of playing, I have accepted that is my limit and so be it.
The main thing about this and any video game is that you enjoy what you do, not sit here thinking you are missing out. No matter how much you play, how much gear you get, what your IO is, eventually it all means nothing and the time spent is all but a memory, make it a good one.