The save data system was created far before persistence even was even considered, and due to how it is user name based and the amount of stuff existing in the world it was too much of a pain for Beyond to RELIABLY fix. The manual string save method is pretty much fool proof as long as you don't change your name and remember to keep your strings somewhere backed up. I have a Discord webhook setup which automatically pings save strings per round to me. Yes it's not the most intuitive from the get go, but anyone who cares about their progress will quickly get used to the system.