Cruft remaining after many distro upgrades?

Since about Fedora 27, I’ve used dnf’s ‘distro upgrade’ plug-in to advance thru 28, 29, …, 32, and now to 33 – never doing a complete re-install. With many software systems (cough, cough, Windows), each major version upgrade leaves left over junk files, configurations, (often well-hidden) temp files, etc. Can anyone comment on how closely the Linux/Fedora major-version upgrade process results in a software config like a fresh re-install?