It wasn't even tech bros. Some people started using opensource software, discovered the master branch and lost their shit. Nobody meaningful had ever connected the name to anything malevolent, but those people made themselves be offended in the name of people who weren't even offended by it.

Microsoft bought github and didn't want the bad press so they renamed it after the twitter shitstorm. The professional victims then moved on to whatever else made noise on twitter and that was that.

I force all new projects to use master as all my old scripts and repos use master. Twitter shitstorms scan stay where they should be: in the toilet bowl of the internet aka twitter.