Bodycams are a bit different. That falls under anything in public can be recorded scenario (in most states). Other than bathrooms and locker rooms, one does not have a reasonable right to privacy while in public.
I’m sure it can get dicey if you record someone whispering at a dinner table at Olive Garden, but anything loud enough to be heard is considered free game.
As a general rule that is true but exceptions can be made. There was a case a few years ago when a man was sued (or prosecuted, I can't remember which) for placing a small camera on an open staircase so that it was aimed up the skirts of ladies walking on the staircase. The court ruled in the ladies' favor claiming that they had a reasonable right to privacy against someone aiming a camera up their skirts.