I avoid reinstalls as well and one of my systems hasn't had a reinstall since Fedora Core 4. This system actually started on Red Hat Linux 8 (the precursor to Fedora, not RHEL). It was upgraded to RH9, then FC1, etc., but I had to reinstall once (I think disk failed during upgrade). I have been able to rescue other upgrades that failed.

I have upgraded literally every component multiple times so it's a Ship of Theseus.