I backup files (images and videos, mostly) to Nextcloud using the Nextcloud app, and sync my contacts and calendars to Nextcloud as well using DAVdroid. For 2FA tokens, it depends on whether I root the phone or not (Aegis authenticator app with backups for when I don't root it).
Basically, the only thing I lose is usually SMS messages since all the other messengers seem to keep message history server side (like Telegram).
Basically, the only thing I lose is usually SMS messages since all the other messengers seem to keep message history server side (like Telegram).