Martin Shkreli (the pharma CEO who gained fame after jacking up the price of a drug by 5000% overnight) is referred to in the press as "pharma bro". What makes him a "bro"? He's awkward, unpolished, and more resembles the overcompensating nerd from high school than the binge-drinking football-playing jock who got invited to the parties.
Tech has never had a "brogrammer" culture. The term is just used to paint the picture of programmers as being misogynistic.
Me neither. I'm not Silicon Valley-based so when the articles started to appear about some guys who pop their polo collars and work out between writing lines of code I just assumed that this is a quirky new meme that is based on a few eccentric characters existing in real life. And a stereotypical google engineer in my mind is polite to a fault and not in any way a brogrammer (I wonder, is this grounded in reality or are my stereotypes off the mark?)
Evidently, the word "bro" is convenient: it is short; it is vaguely pejorative; you can seamlessly attach it to other words to mark the specific bro (pharma bro, google bro etc.)
Fortunately, once Rails grew up and put on a suit and tie, they kicked out most of the toxic people and the situation got a lot better... and Rails even became a better framework at the same time to boot. Just one example of the axiom that "rock stars" and "brogrammers" don't actually produce better code.