I maintain most of my old computers because old flight sims and late-90s games run better on them; EAW and RB3D in particular. There are many games that actually run better on modern systems with enhanced graphics and gameplay. Sadly, many others do not. For those, I prefer to just use an old Win9x system and enjoy them the way they were meant to be played.
I maintain my Pentium MMX system for Archimedean Dynasty, EF2000, and MechWarrior 2 (3dfx version). It's also very good for running old DOS stuff.
I've stopped trying to explain this hobby to others. I get raised eyebrows and confused looks. My advice is just to not mention it at all. At best, you confuse people. At worst, they think you're a weirdo. Nothing positive comes from mentioning this hobby to folks who do not, will not, and cannot understand. During the 90s it was pretty common to see a joystick on somebody's computer desk. Nowadays, people think it's weird. They fear what they don't understand.
Heck, even I don't understand why some folks here collect the things they do or the reasons why they do it. I especially don't understand the under-30 folks who enjoy this hobby. Without the nostalgic aspect of the whole thing it just makes no sense to me. Ultimately, it's just a hobby. Your motivation and reasons for engaging in it don't have to make sense to anybody but yourself. I mean, some people collect these horrible things and display them in special cabinets:
... and then there are these guys:
I just cannot make my brain comprehend those two hobbies at all, but the folks who enjoy them aren't hurting anybody and it makes them happy. So, do what makes you happy and share it with people you like who can appreciate it. 😀