Not everything has to be equally discoverable. By that same logic, the majority of right click interactions are off the table. You can right click window icons in Windows too, with no visual cue either, they just act different and the surface area is much smaller. Titlebars also don't tell you you can drag them, and essential productivity shortcuts like alt-tab are not advertised either.

It's okay to have to be taught some things, it makes it better for pro users when the handholding is minimal.

Here's another one: hold alt when a menu is open to see some options change into alternate versions. Instant feedback, works on dialogs too. Keeps the UI uncluttered for noobs and power users alike without significantly impeding you.