The email + pin thing is a surprisingly useful pattern. Damus adopted a form of it for their website login which is cool. Pushing it further, wonder if the key could be sharded across a collective of providers and you never even see it. It’s just out there.

RE: 2FA… different topic but if you are on iOS the 2FAS app is very nice and clean, open source, and you can store backups in your iCloud account. Not perfect, but better. Been moving off Authy.