I do believe Blizzard has given up on using flying as a scapegoat (that's what this flying debacle was from the beginning, nothing more) but the players that get their opinions from what others tell them at some point, keep parroting it over and over, pretending like TBC, WOTLK and MoP didn't exist. Hell, people IMMERSED themselves pretty damned well in the redone Azeroth that came with Cata as well.
The only thing that ever removes immersion for me, would automated travel. Flight paths. Pretty funny of them to blame flying for "killing immersion" yet improving upon and encouraging the use of automated travel, directly promoting going AFK to take a dump or make a sandwich...
They ended up listening to those of us telling them that flying by ourselves on the back of mighty beasts like dragons, or in fun mechanical inventions like helicopters/rockets, in a fantasy game ADDS to our immersion. I'm very happy about that, and hopefully the Legion system won't give cause to spark another debacle on the subject since I think the compromise is fine. There will always be idiots out there that need to be FORCED into playing the way they want instead of just doing it though...be it only using ground mounts, never using flightpaths, not pvping, not pveing, not using heirlooms, being social and so on...