Personally, I keep old cameras because they still work (the Hasselblad) or the lenses can be used with the latest camera (Nikon-Z with FTZ) I did optical engineering, so they have special meaning.

I keep some mac minis for linux (when I get the time), one old imac to manage the music on ancient ipods that don't seem to be manageable with newer computers, the Cube, because there ain't nothing like it [0] and the IMSAI that is too much trouble to ship even to computer museums, and certain ones, no CHM of Mountain View in particular, don't think it "classy" enough to take. No computer superhero autographed it, I guess.

I have lots of electronic parts and hardware bits that I don't think I'll ever need.

I found over the last 10 years alone, that I spend most of my time just USING computers, with the piano and photography. What I have done is the best guide to what I will do, and need, moving forward. Piano alone could take all my time, but it's for fun/enjoyment, not an obsession or profession.

Everything is under review for the next move.

TBH, in terms of "wasted space" furniture is still more of an issue.

[0] When the capacitive power switch dies, I guess that goes. unless there's an easy hack that I missed. No, I don't intend to turn any computers into fish tanks.