MechaPilot
Explorer
... which is only possible because of said nostalgia.
No. I'm sorry, but there are other reasons that people purchase things. Nostalgia is really only relevant if WotC plans to only sell things to people who have already bought D&D in the past. So far as I recall, I believe there was a statement by WotC that they intended for D&D to be a lot of people's introduction to the TTRPG hobby. By necessity, that means also selling their products to people who have never played D&D before.
In addition to nostalgia, you also have personal preference: some people just like the gothic horror genre and might try the Ravenloft setting if they were already fans of games like WoD or Vampire.