This was a Critical Mass event, which is why the bicyclists are taking up all of the street as a way to reclaim the streets and protest the lack of safety for riders under usual conditions. It’s not legal, but protests are never useful if they’re fully legal now, are they.
The unsafe thing here is the driver who insisted on dangerous driving. Motorists have an obligation to not cause harm regardless of what others are doing.
If I threw you into oncoming traffic would that be unsafe? Simple answer, yes. That’s literally the only point I’m making. A protest being good doesn’t make the handful of troublemakers suddenly perfectly safe. They’re on the wrong side of the road.Travel direction does not change because you’re on a bike. Done. That’s it. Unsafe behaviors by some of the cyclists.
And the driver was the only person making the situation unsafe.