I'd like to know as well, just started playing and reached lvl 82.
Alot of the questlines from BC,WOTLK,CATA are totaly borked and you have to constantly change zones to do what's working there.
I'd like to know how much of the world quests outside of BfA is scripted, meaning WoD,L,MoP.
Was told in Discord that BfA is 100% scripted properly. I can't wait to get there (perhaps in 3-5 days? going at full speed leveling...)