The question is not the money, the question is freedom of speech. A platform taking a commission is no big deal compared to the fact that it is allowed to determine what opinions are allowed and what aren't.
The platform has to determine what it's funding, because it's dependent on (a) local law (b) payment processors (c) the goodwill of the rest of its customers.
Nobody's going to help someone fund their child-porn-to-Iran scheme, and nor should they.
Unfortunately, as long as they're relying on Stripe and PayPal there are 1imitations to what is and isn't allowed: there are plenty of things that US payment processors make hard to deal with.
Not trying to dispute your point, but out of curiosity: Is that actually true?
> Donations to [...] can be paid using: a credit or debit card (Visa, MasterCard, American Express), a Euro bank account (SEPA Direct Debit), or a PayPal account.
Could I send money through my regular European bank without using Stripe to pay on Liberapay? Does anyone know how they've implemented that?
However, Stripe is still a US payment processor, and will be subject to the same legal concerns as other US payment processors (such as those raised by FOSTA-SESTA for anyone involved in any sex work). While you might avoid Visa/MasterCard's rules that come from such a legislative environment, you won't avoid Stripe's.