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.
Seriously, like has that dude never heard of a NIMBY?
Drivers fight tooth and nail to prevent anything from being implemented if it means they incur even the most mild of inconvenience.