I had an affiliate marketing website when I was a kid, mostly for fun and learning with some friends, that made some money off backpack recommendations and Amazon links. We didn't feel too good about it after a while so we shut it down. I now hate SEO powered advice blogs.
More recently, I've started making adult videogames, one of which being an interactive fiction that had a lot of traction, but is now on hiatus due to Covid related reasons. One unintended effect of this, is that I learned personally how much both Apple and credit card providers have a chilling effect on freedom of nudity in entertainment - it's appalling.