And no, "anonymous mixer" services don't work either. They're yet another layer of useless profiteering middlemen, which the web already has more than enough of.
I wouldn't trust anything to be safe from the dragnet surveillance apparatus of FVEY.
The problem is, if you want some "proof of money"/"proof of stake", site operators set that up on their own which is a ton of work and people will not want to set up payments for their favourite porn site AND the government can trace back people from payments to site visits, or site operators contract a major vendor (similar to Stripe, Paypal, ...) who handles it and can then trivially be subpoena-ed for records.