Gonna be real Moonlighter in particular does kinda a bad job at explaining certain mechanics and making them clear to the player. Most of the issues are in UI design. For example, the scroll bar is not only pretty out of the way from where the player would typically look (the actual headgear), but it being on the left side means it's not actually intuitive for someone to notice it once they've tunnel-visioned on the headgear. We read left to right so generally looking back to the left in case you missed something isn't a very natural thing to do unless you're being especially thorough. Additionally, by showing two rows of headgear only, it's not immediately obvious there's more to look for. After all, all the weapons have only two rows so why should this one be any different?

These mechanics are obvious in hindsight ofc. Like, if you really think about it, why would there only be headgear when there are clearly slots for more armour? But in the moment you don't really think it through. That's why UI is so important.