[Oni]

Wouldn't be surprised if their decision has to do with payment processors. Another site will be quick to take their place and there's already existing clones.

Onlyfans? More like OnlyPants har har 

But its becoming a Patreon copy basically? Seems an odd move since its a huge amount of loss for their platofrm

Pretty much. Patreon already serves that niche, and they allow some NSFW creators.