I run into it when using Rider. I have text size increased on my Macbook and Rider has 8000 menu items, so my menu icons (all of which are default macOS, no third-party stuff) will be hidden to make room for Rider's stuff. I have to switch over to another workspace or window (i.e. away from Rider) if I want to access one of them. It's annoying but I'm not sure who I blame here; Rider I guess, for having a zillion menu items.
Screenshot: https://imgur.com/8y0QbZN
The gap between "Run" and "Tests" is the notch, which I don't usually notice is there unless I'm in Rider.
Why not blame Apple for having a busted-ass menu bar design? The behavior of "if the menu is busy, icons just disappear" and advice like "apps shouldn't rely on menu bar icons" are just bad ideas. They don't work well with how people use computers or how developers write apps. It's a bad design.