Realism is fine if carrying it out in game is not tedious. Like I said before, just having one command "take care of your equipment" which would make your character clean clothes, clean guns and stuff. That's fine. Having to click something ten times is not. It is like you had carry out all the tasks in Dwarf Fortress manually. "Press button to smash the metal bar with the hammer. Hammerstrikes left to produce one dagger: 58".
This! So much this!
If you want to include overhead for equipment and such, that's fine! More challenge is always great, especially if it can be optional. But nobody has fun pressing 100 keystrokes to do completely mindless tasks even if they appreciate that those mindless tasks do need to be done.
I'd rather have a 'maintenance' time that you would spend before sleeping, or when performing a generic 'equipment maintenance' activity. Carry more guns and wear more clothes, the maintenance task takes longer, or needs to be done more often. Keep less equipment that requires maintenance, or gain skill in skills that affect the maintenance you're doing, and it takes less time, or needs to be done less often. Then it become a gameplay mechanic, something that can actually be balanced, unlike tedium. Currently there's no 'challenge' or 'strategy' required for lots of these maintenance tasks (filling mags, eating, drinking, reading a book, washing clothes, maintaining firearms (is this actually a thing in the game now?), etc...
The fact that you can't make gunpowder just seems silly, as others have pointed out, when you can literally make a Plasma Rifle out of spare parts, create complex biotech out of corpses, and forge a high quality sword with a souped up charcoal grill and rusty scrap metal!
I know the dirty clothes thing was a big deal for some people, and if I recall correctly at first it wasn't really easy to disable. I agree with most other people that the whole thing is just another unnecessary element of tedium, but if it's optional then who really cares.