It's very difficult to revert to a backup if the system is trashed
and all you have left is TOS.
this is again not true. All you need is mint.prg, xaaes and ext2.xfs (stored on diskette, CF card, anything). If your system is trashed (its unix side), you can change INIT= in mint.cnf from /sbin/init to let's say xaloader.prg, i.e. activate GEM and browse filesystem manually (and fix the issues if needed). So don't blame Alan / mint, it's just lack of your knowledge (which is OK, people are here to help but "mint upgrade sucks" isn't exactly the right attitude to ask questions / solve problems).
Been there, done that with far too many systems. I've done Ubuntu updates
that trashed the system so bad it took two weeks of solid effort to get
them back to usable.
Again, lack of knowledge. Proper choice of partitions and safety precautions can't take you more then 2-3 hours even for complete reinstall with all your customizations and additions.