Let us stop pretending there was a hill for it to go downhill from in the first place.
Vanilla: “So yeah, bad guy, Yeah, really bad, we should totally do something about the Frozen Throne” “What Frozen Throne?” “The one in the Third War, duuh” “Where is that on the map?” “Holy Hell, it has actually vanished, also, where the heck is Quel’thalas?” “Yeah, shall we just have a Cold War stand off, and uhhh…dragons and stuff?”
TBC: “Oh Hello, there’s Quel’thalas, and wow! Aliens have arrived!” “This is nothing new, this is the basic premise of the whole franchise! The orcs are Aliens!”
“So uhh, what now, shall we go and deal with the enemy of life who has laid low a continent and plots our demise?” “Naaah, lets jump through a portal and go beat up a cripple”
WotLK “Guys! Guys! I’ve found an old map! It turns out that Northrend, which we knew existed and have been to, actually does exist, we can go and fight the guy we should have been fighting since Vanilla!” “Yaaaay!”
Cata: “Holy crap! I didn’t know Dragons were that scary, apart from the times when I knew dragons were that scary, but this dragon is definitely scary, He’s blown stuff up! Nobody blows stuff up apart from us! Let’s kick him in the nuts! Yaay, world saved!”
MoP: Actually, I’ve got nothing, that made perfect sense, as it was an entirely new canvas to work with…Can’t really fault that.
WoD: “Time travel! Alternate Realities! Alternate People! Oh Noes, one of the Alternate people is now paying attention to our reality and timeline”
Oddly makes more sense than Vanilla, but moving on…
Legion: “Legion Invasion, everything is horrible, lets chuck a couple of PvP things in there, because that makes -complete- sense during a fight for our survival. Oh wow, turns out that the Cripple we went to beat up during TBC survived, and the Night Elves killed other Night Elves to let this guy out! (Night Elf fans can now officially stop whinging about Teldrassil, because you make no sense) …Wow, who knew, Sarcasm and a Smug grin are more powerful than being able to actually see the frickin’ future, and that blinding yourself, actually means you can see more than you did before! Whoo!”
BfA “Lets go…fight…” “Why?” “Because a teenage Goth had a tantrum moment and set fire to a tree”
Shadowlands "We’re in the Realm of the Dead? This…kind of sucks, is there anything we can do to make it suck less? Oh heck, look out, the teenage Goth is back, what is she going to burn this time? " “It’s OK man, Life is a prison, and she will set us free…”
“Helllo? Anyone at home? Prison…Jailor…Jail, Prison, How does this work?”
So lets not pretend there was a golden age of lore and immersion, because there really was not…