I’ve been asked a handful of times if it’s okay to upload things that aren’t games to itch.io. (I’ve been asked about things like ebooks, tools, and visualizations). I’ve said yes, but one of the problems is that itch.io calls what you upload a “game”.
Starting today you can customize what itch.io calls what you are sharing/selling. You can find the “Custom Noun” setting on the game edit page, it looks something like this: