I don't think combat and travel trivialization are the same. But I don't think you do either.
I think it's especially a bit hypocritical when they also throw around those really fast ground on-use items like the fast yaks and what-not that barrel around at 400+/whatever %. Those also skip a lot of travel time and get you past a lot of grounded combat quickly, so why is flying so special when these are allowed so frequently for so many expansions - I mean hell they've been around since Mists in every expansion at this point.
And if they want us on the ground so much why isn't ground speed just increased to these levels so travel isn't so arduous and whatever holy ground experience has to be maintained can still be there? It just seems really weird that there are clear answers to this problem they even have implemented for many expansions but aren't making use of.