I'd prefer to get a VPN to avoid the risk of my internet getting shut down, but I'm not aware of what the options for Linux are. I figured this would be a good place to ask.
The only VPNs which are not owned by marketing companies are Mullvad and Proton. The largest VPNs are owned by Kape Technologies, renamed because their prior company name distributed malware, whose top people are former Israeli military, so I wouldn't trust them as far as I could throw them. I would never use a free VPN except for Proton, and Proton's paid VPN has a lot more nodes and features.
That only benefits the Mozilla Foundation and not the Cooperation who is responsible for developing Firefox. If you want your money to be used for Firefox, then you need to spending it towards the Cooperation AFAIK.
IVPN doesn't do any kind of marketing, none... And Windscribe is FOSS too ( too bad it's US based tho ), another one I can think of is TorGaurd ( proprietary ), they received a court subpoena but they revealed nothing about their users ( they don't keep logs )...