There's plenty of races and subraces already added by mods (like genassi) but they don't have the reactivity that official races/subraces have, that's the downside.

I know they did some DLC's for DOS2 but I haven't played them so I'm not sure what the content is (but I believe is not that much)

''They don't have plans right now'' is what Sven said but he also said they are waiting to see how the game does (same as WotC I would assume) and then they'll see what happens. I don't see how if the game does good (and probably will) WotC is not gonna try and make more money with BG3.