I ran FreeBSD on a 486DX2 with 128Mb of ram .
It ran X11 and twm window manager , but no DE. Ran netscape browser.
I used that machine (actualy 2 of them) from the mid 1990’s to about 2012.
Took about 3 minutes to boot. It was FreeBSD2.x
So I think you can meet the challenge of revitalising that old machine. You may need to dig up old distro versions to get hardware support. Most of todays distros have dropped support for very old hardware.