Mullvad is one of the best VPN services accepting Bitcoin, and privacy payments with Monero, but there are other good alternatives.
I recently tested new decentralized VPN service
NYM, and I think is very good for privacy, it deserves to be added on this list.
NYM is accepting Bitcoin, Lightning Network, Monero, Liquid L-BTC, L-USDT, Nym token, with 50% discount.
Another good service is
LNVPN that is accepting Lightning Network, USDT/USDC and other coins.
Note that Bitcoin mainnet and Monero payment options are currently greyed out.