It would be nice to have a feature that will allow hide these invasive apps via UI, like it’s done on iOS, for example.
I know that the issue comes from the fact that applications ships unnecessary “.desktop” files but users have no control over them. They just install Firefox, Chromium, Wireshark, etc., and already there are quite a lot of annoying icons due to dependencies, etc.
A user could also tuck unwanted app away into an app folder. Drag an app icon on top of another to create a new app folder.
That said I agree it would be nice to have this functionality built in. I remove 2 dozen .desktop files from my install for the same reason. I figure one hurdle is, how do you unhide apps? The above extension does that through its settings so maybe a Settings panel.
It’s kind of hard to add a way to hide an application from the Shell launcher UI, because there’s no mechanism to undo that operation after a while.
In your specific case, those tools should not have desktop launchers to begin with; they have one because they were added back when there was a menu, and applications could “hide” launchers inside sub-menus. It wasn’t a good idea either, back then, but at least it was less visible. The switch to a grid exposed all the bad practices that some application developers used.
In theory, it could be feasible to add a “show in the applications grid” switch in the application’s page inside Settings; but it’s hard to establish a connection between that page and the applications grid to begin with.