I've cancelled my subscription yesterday, conveniently it was about to renew at the end of the week, so I have a few days to migrate from Proton, here's what I'm thinking of, but I'd love to hear what other people are switching to
You can export your Aegis 2FA tokens and import them into a couple of different Linux desktop programs, including OTPClient.
https://community.linuxmint.com/software/view/com.github.paolostivanin.OTPClient
This allows configuring "one" MFA token with each service, but also having it on one or more Linux computers and even on multiple Android devices (Aegis can also import.)
I imagine it is unwise to go nuts with this. Each place the tokens are at carries some small risk.
But I feel much betfer having mine in two places than in just one.