I feel like once they went under, that's when hell was released.
I don't think it was any one thing.
There's a certain level of one-upmanship and a slippery slope when it comes to anything fetish related. You start to want things a specific way. But not everyone wants to or can cater to it, and your slope might go a different direction.
For example, I'm into TF/corruption. I like my good girls going bad and wearing skin tight clothing doing it. Maybe turning into monster girls or demons or whatever along the way.
Well, one problem with the fetish is it's closely tied with furry, NTR, and futanari. And any time a game gets made using crowdfunding where the dev offers stuff in the game at higher tiers, you end up with a "Latex Skunk" problem.
To clarify, I don't necessarily mean ACTUAL latex skunks, though I have seen them pop up a lot in games they don't belong in (like a game about robots) thus the name i've given for the phenomenon. But the idea is that people will try to insert their fetishes into things, and they slowly escalate over time.
So we get tits big enough to function as explosive devices that can destroy cities because a buncha people started escalating.
Even what we consider "normal" has gone up, with C and D cups being the size du jour.
And the fact people will pay devs/artists to draw their OCs with back problems and proliferate the issue...yeah...