Netherdrakes are dragons warped by fel magic. Normal dragons have horns, thus netherdrakes should too.
If you look at old drake models they all used the same customization, yet the new drakes we have in dragonriding have a wide range. So it’s just that really.
That’s why I still play this game 
This might come as a surprise to you:
Outland took place in the year 26. Dragonflight takes place in the year 40. Canonically 14 years have passed since we last encountered Nether Drakes.
In that time, Sabellian hatched and raised an entire new group of black dragons. Nether Drakes came from Black Dragons.
Logic is not hard to follow that in that time, more nether drakes probably cross-bred further with the new black dragons and other dragons on outland and created new hybrids.
It’s been a decade and a half since we last saw the Nether Drakes. They will have changed.
I don’t like the horns at all. It seems so often with mounts that would otherwise be amazing we get these baffling design flaws that are too prominent to ignore. Hopefully they intend to branch this into customization options. I feel that the spike on the original models contributed to the unique and streamlined look.
They’ll probably turn up on the Trader’s Post with horns in the future.
Am I too late to mention Nether Dragons?
I already mentioned them. The lazy recolors for old drakes since they didn’t have a model.
… When you notice that netherdrakes are in fact unicorns.
Oh right.
At least Hearthstone is offering some new designs to the dragons. Doesn’t seem consistent though. 
Maybe you’ll be able to customize them eventually.
Hearthstone has some good stuff. They are, however, non canon until it is. Maybe this is the case, thankfully they didn’t remove the shark like aspect completely like they did in hearthstones.
Drakes can have horns.
You’re welcome.
I don’t want this. please put it back in the oven until its done. Netherdrakes have fins.
This one has fins as well? The tail fin is there just like the original
The big difference is this one has two horns on the side of the head, rather than the single one on the top of the head the rep ones have
I despise how people constantly try to use reductionism like this. Don’t do this crap. You just become a subversive element, poisoning the internal consistency of the universe you claim to enjoy.
But to the OP, I will say, the appearances of the Netherwing were never really explored fully in BC. Their large full dragons were just teal ephemeral normal dragons, no hint of a difference from a regular dragon. The way they were so radically different from their, I guess adult form? It hints to me that they just didn’t want to focus on fleshing them out at the time, they just wanted us to be able to ride some dragons since flying was added, and they didn’t have a way to justify a regular dragon mount. Showing a new Netherwing drake with horns isn’t a bad thing, IMO.
Because Trading Post stuff probably isn’t that deep.
The art for Hearthstone is usually canon. It’s the flavor text that is not.
So why is the rest of it okay but heaven forbid a dragon as a fin over a horn as if that is going to ruin the narrative in the slightest…
I’m saying you can respond with a counter argument to OP’s claim, rather than reduce everything to its simplest form to try to disqualify criticism of the subject.
Following reductionism to its logical endpoint, literally nothing matters, nothing is worth anything, and nothing was ever meant to be anything. It’s inherently a nihilistic thought process that is nonsensical and literally ruining fantasy as a genre. If nothing matters, why not just go ahead and have a 1972 El Camino as our next raid drop mount from a raid boss made in the image of Dale Earnhardt? That’s the stupidity of reductionist argumentation.
Well here I am to tell you I was wrong and jumped the shark.
They have full customization, including the proper no horn and head fin version.