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.
Wow, you really like your wordplay, huh.
Whenever something makes the news or the rounds on social media, this is your opportunity to advocate to other people for the correct “thing,” whatever that is. … Which you are presently not doing.
“But is that why they’re blocking the road?” Yes. Yes it is.