I wasn't even playing WoW during Warlords of Draenor, but I still remember the big hubbub about the idea that Blizzard was considering not having flight in that expansion. It was just being talked about everywhere (as you can see from the "here's what other bloggers are saying" section in the linked post). At one point I considered reviving the blog purely to tell everyone that I thought they were being stupid, but fortunately I had enough sense not to do that. I don't think that lecturing devs or players of a game you're not actively playing about how they're doing it all wrong is a good way to spend one's time.
What I was thinking though was that I found both the complaints from players and the devs' attitude annoying in their own way. As someone who fell in love with WoW in Vanilla, back when there was obviously no flying, the wailing about how the game was literally unplayable without it made me roll my eyes every time. At the same time though, I didn't get why Blizzard were being so weird about it with these arguments about how flying supposedly trivialised the content. It's possible to design things like questing with flying in mind, and I had seen them do that in both Burning Crusade and Wrath of the Lich King; why were they suddenly acting as if they couldn't do it?
In the end we got an awkward compromise in which Blizzard still designed the content for ground-bound play and then would let people fly over it by the end of the expansion after they'd "done their dues", as if questing was some sort of chore and AFK-flying through a whole lot of nothing while ignoring all the action on the ground was some sort of amazing reward. Because make no mistake - letting people fly in content that was designed around players being ground-bound does mess things up.
Playing Burning Crusade Classic was actually a good reminder of that, because while it did have content designed with flying in mind, the early levelling quests generally weren't, and if you went back to those with a flying mount later, they were kind of dumb: the stereotypical situations where you were supposed to fight your way through an enemy camp but would then just fly over it to pluck your objective straight out of the air.
Blizzard's decision to design Dragonflight with flight in mind from the very start has been a huge sea change after all those years, and to be honest it's been great. Aside from the first few intro quests, everything is meant to be done with a flying mount, and it really shows. There is more verticality than we've ever had in WoW before and it's very fun.
The fact that dragon riding functions differently from normal flying plays a huge part in this as well. In my opinion dragon riding is honestly so much better that it makes old flying kind of feel like a mistake in hindsight to be honest, with its slow and boring "swim through the air" mechanic. Dragon riding isn't difficult, but it does take a bit of practice to get used to, and it does require continued engagement, meaning that travelling is part of gameplay instead of "time to AFK" (though flight paths still exist if you do find yourself wanting to go for a bio break while flying from one end of the Dragon Isles to the other).Actually engaging with the game while travelling in turn gives it meaning and opens up opportunities to get distracted and sucked into other activities. It's kind of like the travel in Vanilla, where crossing the landscape would give you a sense of scale, and while doing so you might find yourself discovering something interesting by the side of the road or running into other players. This isn't to claim that Dragonflight is totally like Vanilla (please don't @) me) - it's still a more modern game where everything is much more fast-paced and requires more key presses, but my point is that the vibe in the open world is similar.
Often when I log into retail and fly across the Dragon Isles with a certain goal in mind, I'll end up soaring over something interesting on the ground and landing to pick it up, then I spot a rare just a little bit away and go to that instead, and before you know it I've almost forgotten what I meant to do originally and been playing for much longer than I intended to. This is not something that happened to me in Shadowlands, but it's definitely something that has happened to me in Classic and I'm digging it in Dragonflight too... even if it means that I'm often spending more time playing it than I had planned.