I will say Stormwind (At least on MG) is certainly more active, but that’s also stuffed with way more things than Org has. There’s still usually folks hanging around in the Valley of Honor doing stuff!
I think folks are starting to transition away from there, though, which I think is a good thing since the Valley…sure doesn’t have much. Not even chairs.
Silvermoon, I can’t speak on, a gob doesn’t usually have much business doing elf stuff. Heard they hire leper gnomes. That’s gross.
Most RP is done in game. The Discord is mostly used to advertise and organize events for those who would like to participate. As I said, it’s difficult to get word of things like that happening out in game. And anyone can join up!