Because the players don't want quality <sarcasm>
Blizzard, I demand that you devote endless hours on these mounts in order to ensure that they are unique little snowflakes. I don't care what else you have to do...rid the game of transmogrification, if you need to! Just make sure these horses are armored by 4.3 in the name of quality!
That too, was sarcasm, in case you missed it.
Be honest: that's the problem. People are makin' a big deal outta this 'cause you made a big deal outta this.
Last I checked a two paragraph post about the new mounts (particularly after people had been QQing about the mount imbalance) is not making a "big deal outta this".
But my argument is, you did a lot of work on Goblin mounts and now you're just tossing out horses, calling them "Gilnean" and forgetting about it.
It seems . . . biased . . . and I've never blamed Blizz for Horde bias before. And it also seems lazy.
And Worgen also get an incredibly cool feature called "running wild" which is totally unique to that race.
It seems "lazy" because it's a quick fix for a problem that many have been whining about. And they've been whining about it, not because they wanted an awesome new mount for the Worgen, but because they wanted an equal number of faction mounts.