By the beer standard the most tech-bro-y place I've worked was Swiss Bank Corp / O'Connor in Chicago, a software focused trading shop. In 1994. NeXT machines and Symbolics LISP machines on the private trading floor kind of place, with refrigerators kept stocked with free sodas and beer. Beer was for after 5, except on St Patrick's day, when coolers of beer came out at about noon. Also, Nerf guns on the trading floor.

And yet, at least for the people I know best from there, they didn't turn out to be tech bros. Perhaps there's a generational aspect.