Vanilla is more the MMO-concept then BfA or previous expansions. Sure, you can be a nobody and hope to find a group to go to a dungeon with unreliable people, or you can become a respected member people want to bring when they are looking for 1-2 more.
BfA is a glorified instanced server system with a shitty waiting room. If you want to do a dungeon, you just queue up, hope it pops quickly and press yes to be teleported and then you don't communicate and if you don't wipe, you just do it again. If you wipe, you blame the others, because obviously, you as the god gamer can do no wrong.
Part of the enjoyment of vanilla is that you can run dungeons over and over, and you will probably run into the same people in the next dungeon too, start talking, start remembering, and then you hit 60 and maybe you join each others guild or do dungeons runs with two different guilds depending on what type they are. It's not this streamlined experience as it is now.
There are isseus with vanilla, no doubt, however, the roughness is also what makes it charming.
I guess the dungeons in Cata can come close simply due to how shit they were.