Reason CoC ended up getting abandoned was because Fen got bored and wanted to move on until people bugged him to finish it and we got that awful final dungeon that was half baked. Again, that is because the game is named as a sequel to an already established product.
Coc was abandoned in large part because it was a mess. Fen was making it all up as he went. The code was apparently hard to work with, there was no clear plan or outline, there was content that couldn't be touched because it's authors ghosted and Fen didn't want to ruffle feathers, and a long lost of other things.
TiTs was Fens shot at to take all the things he learned and apply them from the beginning. And despite not being called CoC, TiTs got huge.
More successful than Tits? That is a bunch of bs because tits had a kick starter and a patron that brought in so much money that it is crazy.
It wasn't a Kickstarter, it was a porn crowdfunding site called Offbeatr. I know, because I was in on it.
It made 200k. Quite a bit...but that's, like, a few months Patreon income. For a game that's run a Patreon for like 9 years now, not much.
Steam visibility alone ensures that CoC2 is way bigger than wither other game. 16k people bought in in the first month, and that was almost 2 years ago now. CoC2 is way, way more popular than either game ever was.
More popular than CoC? I guess? CoC 2 is a newer game but at CoC's peak I highly doubt it because it was the first of it's kind.
Being the first if it's kind is exactly why it was the least popular. It had to build its fanbase from the ground up. TiTs coopted the fanbase from CoC and built on that, CoC2 took those and built on them. Every one of these games is bigger than the one before it for that reason.