There's a subset of ideas and culture associated with "techbro" beyond just being interested in technology. Obnoxiously Libertarian, overly analytical (lack of holistic perspective), crypto pumping, sometimes pretty racist/sexist (though I would say that's a subset). It's a particular cultural strain of people interested in software, not all young men who code.

These people were "finance bros" working in hedge funds before the VC/startup industry took off, and crypto became the most popular way to scam people.

Edit: actually the "overly analytical" might fall more into the stemlord category, who routinely get mislabelled as techbros.