And yes, they could relocate to TOR, I2P, use P2P websites, torrents, and only accept cryptos for donations. But eventually you'll need to put down a credit card on file to buy a domain, and that domain needs to be owned by somebody.
You don't need to pay to host onion websites (.onion domains are free and have no central registry). Though that of course really limits the possible outreach, because most people are not used to browsing onionsites.
The issue is, now they are the legal owners and liable for the content of the website, and they also support PayPal, which will absolutely drop them the moment they get sanctioned.