This is going to be corporate suicide on a greater scale than Tumblr's policy. I say greater because OnlyFans is/was still on a massive upswing whereas Tumblr was 10 years past its peak already when the nails went in the coffin. Edit: I understand this is supposedly not their choice.
Also, weird that they would give up an entire market because of prude payment providers. Are these providers from Afghanistan? They should not have that much power over their customers.
Maybe a crypto spin off could work.