You don't necessarily need one for just developing the film - dark bag to load the film onto the spool which is lightfast and bob is your photographed uncle (source: me, having done this in very un-dark kitchen twice.)
I suppose if you want to make your own prints, that probably needs a darkroom but you can get a film scanner cheap and print them on a colour laser, inkjet, or even one of those Selphy dye subs in lieu of that.
This is what I have done. 35mm bw and color developed in a dark bag. Then scan the negatives. So much cheaper than actually having it developed professionally. You also get to mess with the development conditions for various effects.
I hear you. My process is cheapest, doesn’t require chemicals, can be done in sunlight, and with some glsl knowledge, essentially the same. Only digitally and for $0.000000001 an image.
Yeah, I do that too but since I'd never really owned a 35mm camera, I thought I'd give it a go ("how hard can it be?" "very if your spool is wet, you fool") and I've enjoyed the experience of taking my PEN-EE around and developing its weird little half-frame outputs.
B&W negatives are easy enough at home. Though you have to get them into a computer and, at that point, I'd sort of be "Why bother?" (other than a fun retro weekend project possibly). And, yes, printing requires an actual darkroom. After school, I quickly decided that setting something up in spare half-bathroom was for the birds.
