[vxnul]

"Bro" is a strange word, because it has gone through quite a bit of semantic shift. It used to refer to a certain type of entitled, right-wing young male associated with some college fraternities (not all frats are like that, but a lot of them are) and tech-company management. Now, "bro" has just become a synonym for "man" and doesn't really have the sting it used to have.

[clairity]

then maybe you're too young to remember that for decades it was just an abbreviation for 'male sibling' mixed with a little "close male friend who's like a sibling". 'bro' has basically completely supplanted 'dude', which waxed and waned before it, and like all fashion, it too will wane.