That was a Millennial generation thing. Back in 2002, "Be Your Own Brand: A Breakthrough Formula for Standing Out from the Crowd" by Speak and McNally, was arguing for that. They pushed heavy self-promotion. That got us the "brogrammer", "move fast and break things", and startups that tried to buy market share with venture capital.

I don't see the connection of the brogrammer's to the idea of being your own brand and embracing the weird. To me, the brogrammer's were the result of the huge influx of money into the tech ecosystem. It was the arrival of those just chasing a paycheck and stock options rather than those who enjoyed programming for its own sake.

The things you list seem completely unconnected to me, and not driven by people embracing weird. Stereotype "brogrammers" were very similar to each other.