> Any recommendations on how to start a life as a digital hoarder?

Step 1: Get a NAS or whatever, and copy over things manually when you know you care about them.

That's pretty much it for at least some basic protections, and not starting a whole project. Just made checksums before you send it, and verify the checksums after you send it, and that's pretty much it.

Then step 2-6 can involve doing encrypted off-site (cloud) syncing of your backups, automatic backuping and so on, but as a first step, just do something small and easy, so it won't feel like a hassle in the future.

Hard disagree about the manual copying. I did that for years and that is how you get a mess. “Did I back up that project? On what date?”

You will inevitably omit something you want. Just rsync the entire home folder as a first pass backup strategy.