Which is still strongly preferable to getting locked out of everything because Google Authenticator refuses to participate in device backups. Lucky for me I found out about that well before I moved to "2FA wherever possible", but I still had to send some vendors scans of my driver's license to get back into my accounts with them.

Maybe they've fixed that since then, but I don't care. I'd rather risk a theoretical flaw in Authy's E2EE than risk getting screwed again, and by now much more thoroughly, by the flaw I know about in Google Authenticator.