I had nostalgia for WoW from days spent playing as a kid, but the memories I made playing this version are far more dear to me.

I think that is at least partly because vanilla has so many things that make it unique that I just prefer:
- weird talent trees, especially the druid’s balance tree (omen of clarity supremacy)
- “endgame” starts before max level
- leveling/questing isn’t guaranteed to be a cakewalk
- classes have things that they alone can do (warlocks can summon players, druids can battle-rez)