How robust against spam should side projects be?

I am just getting into making my first project as a hobbyist, and it involves user image uploads. I can imagine a whole host of issues that platforms deal with, from spam to AI to nsfw. Integrating captchas and image analyzers, etc, all feels like overkill. Leave it be until I need it seems like the right answer, cart before the horse assuming it'll even get any traffic or attention, but it's a silly enough joke idea that I want to see if it gets shared around a bit.