It's organized.  We had the same "rally" in my city as well, with everyone holding a sign of a black trans person who had "died" due to "oppression".  They just send out bulletins to these groups of what their cause du jour is, and they "protest" accordingly, complete with ready made signs/ placards. Ever see that Jeremy Piven/ David Spade movie PCU?  About the college kids protesting everything? Yeah, it's just like that. Literally scripted.