The two main problems I ran into were 1) software support at the application layer, and 2) video driver support. There is a herculean effort on the part of package maintainers to build software for distros, and no one has been building 32 bit version of software for years, even if it is possible to build from source. There is only a very limited set of software you can use, even CLI software because so many things are built with 64 bit dependencies. Secondly, old video card drivers are being dropped from the kernel. This means all you have is basic VGA "safe-mode" level support, which isn't even fast enough to play an MPEG2. My final try was to install Debian 5, which was period correct and had support for my hardware, but the live CDs of the the time were not hybrid so the ISO could not boot from USB. I didn't have a burner so I finally gave up.
So I think these types of projects are fun for a proof of concept, but unfortunately are never going to give life to old computers.
[1] My first broadband connection was in 1998 at 768/768 kbit symmetrical. My first megabit speed connection was in 2006 or 2007. in 2010 or 2011 we got VDSL and it was 16 whole megabits. Now i have 300mbit on a good day, and 150mbit on a bad day.
I literally wrote the guide on how to use old hardware with VM tech to route your house, first with ipcop[2], then generically[3], and just this week i wrote a guide on how to get ipv6 working with starlink and dd-wrt[4].
i've been in this a long time.
[2]https://web.archive.org/web/20220323223325/https://www.dslre...
[3]https://web.archive.org/web/20131214075417/https://www.dslre...
and the dd-wrt starlink one from this week:
[4]https://nextcloud.projectftm.com/index.php/s/4iScqZbrfYiNcKy
ETA: it is hilarious how much pushback i got about doing all of this in a VM, just scant years before "you should just use a VM for that" became the default answer, and a decade before "just put it in a k8s cluster and pay someone a quarter million a year to babysit it" became a thing...
also ipcop booted and installed off a single floppy forever