Sure, it's possible. I could do it by hand, but the more clients you want to add, the more cumbersome the process. What I'd like is a tool to automate what is mostly a templating process.
Skyline
Thank you for sharing this story. I've recently watched this video on MLMs and it describes exactly the kind of situations your mom found herself in. I thought these MLM schemes were bad before, but I had no idea just how horrible they actually are...
Just keep in mind that sd cards can also stop working. I would encourage you to keep at least two separate copies, ideally one on a different medium than an SD card, and check regularly that you can still access the codes. A backup is only as useful as it is easy to restore.
The author does a pretty good job of explaining the potential problems this technology could cause. Scroll down to Why Attestation Is Bad.
I don't like it because it has become very iPhone-like in the bad ways, meaning it takes several clicks to do simple, common tasks. I much prefer Samsung's OneUI for how easily accessible everything is.
Cloudflare works really well and has a good UI. Namecheap also works well, but it takes more clicks to adjust DNS records.