I'll jump on the bandwagon of perception, here.
More and more I, like the OP, can't find a game which I like.
But lately I realized that it is because I've become incredibly picky.
I've read someone citing milfcity here as example. AFAIR that is the game with stunning good renders, good animations, and the crazy sex and incest obsessed mom (who I found kinda creepy, btw). (if the game I'm talking about has a different title, that's the same for my point).
That's a good example. When I started to discover the world of porn games, if I had downloaded immediately milfcity I would have been impressed.
Nowadays? Yes, the graphic impresses me, but the game and the story? Not so much.
It's because I don't like incest anymore? No, I'm still a sucker for that kind of story.
But, having played others of the same kind, it doesn't stand above them, or even below them (in a "so bad it's good" way), it is just at the same level of the others. And I have even stopped to check updates. And that happened even for other games.
But, you see, I can say that these games are at the same level of others because I've tried others already. If I hadn't had something to compare them with, I wouldn't have been able to create that comparative "level" in the first place.
So, a long story made short: the games are there, we just aren't interested in them anymore.