> If I'm faced with a major upgrade of an LTS system, I usually choose to reinstall from scratch, shedding packages I haven't needed for a long time with it. But that happens every couple years or so.

This goes back to my original point, which we've drifted a little from.

Ubuntu has more unexpected behaving when upgrading than Debian.

A working dist-upgrade should not be something that your OS struggles to provide. Asking people to reinstall their OS isn't an acceptable answer.

Upgrading should not be a lottery.