To summarise: use a terminal server system if you can, using a desktop for the end user that can be made to behave like windows (or another concept that works for your demography), and have the whole setup in a NixOS configuration that you manage in git.

I see that https://github.com/ltsp/ltsp is still going strong.

An exceptional piece of software in so many ways, created by a very special person. You are missed.

:wq!