It's hard to say. If Postgres is working for you then it might not be worth the trouble. Not everything migrates one-to-one between database vendors.

Fly.io takes daily snapshots of your server volumes so that's one approach to backups that's already handled. However, you can lose up to 24h of data since the backups are only daily. Postgres has some options for streaming backups like wal-e. That might be worth checking out depending on your needs.