Offsite backup is not optional for anything important. It’s worth paying for AWS or literally any other online storage solution for that copy. You don’t want a natural disaster to lead to the loss of all your life’s photos for example.
I also personally don’t recommend doing your own software for anything related to backups, you can’t test edge cases easily and it could easily lead to loss of data. I once used an app that attempted to manage its own backups delete it’s online backup when it lost its local data as it attempted to back up the blank local data.
I miss the old topic specific internet forums so badly, but having tons of different accounts made the barrier to entry high so I understand why they died out.