If i turn on safemode, RouterOS remembers the 'before state' and resets to that state
if I log out/ get disconnected before turning safemode off.

That's fine

But is there a way I can get a diff of the point I got to in safe-mode before the rollback?

Safe-mode in small increments may not be ideal. Sometimes one would want to make a number
of interrelated changes and commit them only as a whole. and when that does not complete
(due to a disconnect etc) all changes would be lost. It would be nice to be able to recover them.

Or in general, it woudl be nice to have 'restorepoints' one can roll back to, and export (even if a later change is currently running),
so that one could do diffs of the exported configs to isolate what changes were made, as examples etc