Personally? Unless I am going from one version of a distro to another (and even then), I have always found enough gotchas and issues with preserving /home and /var that it just never seemed worth the hassle. Much prefer to take the approach that any documents and media are backed up to a NAS (or even just google/apple/whatever drive), config files are part of a private git repo, and any development I am doing is regularly pushed anyway.
Can see the benefits for managing a lot of users (and I do get stuck doing that in my day job) but… you aren’t distro hopping under those circumstances.