I've had several crashes many which seemed to happen randomly or while really laggy and 2-3 times during Moon Lord and the latest crash ended up with corrupted world but other data was still fine, I've already restored from back-ups. (Would it help to share this corrupted world data too if it happens again?) I didn't want to risk overwriting any of my good files with corrupted data, and just what files are really needed worlds, characters, maps, misc. (First time I've ever got corrupt data on the ps4!)
But I think everytime or most of the time when I try to restart the game I get app won't start unless I upload then delete or just delete or some videos, and I know I'm low on free space.
I also think most crashes happen before or while it is trying to auto-save, so maybe if there isn't enough free space it can't save and it crashes or something, but one question is how does it save? Does it just overwrite the data or does it save something like a new temp data then overwrite current data?