I'm not a game developer myself, so I don't know the exact details, but as far as I understand, Itch takes 10% annually if creators leave their revenue in their Itch account without requesting a payout.
In other words, creators are made to earn money for Itch, and Itch refuses to pay out the funds based on "payment processor policies," taking 10% of the frozen funds each year. After 10 years, 100% of the funds end up belonging to Itch.
Itch needs to find alternative payment processing methods so that creators can receive their earnings.
Otherwise, it’s no different from exploiting creators to generate penalty money for Itch.