Okay, so.

Angle grinders come with a hand guard around the wheel, as shown in the attached photo. Now, a hand guard isn't a bad idea. They help control sparks, give a place to set the tool down before it fully stops spinning, and, well, guard against wandering fingers.

The problem is that in practice, folks almost invariably remove these hand guards. I have for my personal tool, and they've been removed on every grinder at my workplace. Quite simply, the guard always gets in the way. Even when doing perfectly routine tasks with the tool in a convenient position the guard causes interference, and this problem is magnified when there's other parts of an assembly in the way.

So the way to make a grinder safer would be to make the safety guard smaller. Make it small enough to almost never be in the way -- as small as possible while still protecting areas near the tool grips.

But of course that'll never happen. Not only is it counterintuitive, manufacturers are terrified of legal liability and it's easier to slap on a sticker that says "don't remove the handguard", even knowing it'll be ignored.