I have resisted moving off Authy as I liked the idea of cross-platform cloud sync. That'll teach me. Any other suitable alternatives? Aegis is android only. I do run vaultwarden, but it means I need another 2FA to login to it, before I can use it as a 2FA for other sites.
KeePassXC (and the associated apps) can store TOTP, and you can sync it with SyncThing on any device. Add an always-on NAS with SyncThing and you'll always have an up-to-date vault, even when your other devices are offline.
2FAS - https://github.com/twofas and I did replaced Authy with it some year ago; I'm using it mainly on iPhone while having a backup file on desktop and second app installed on Samsung phone