"The shutting down of speakers is a small minority on the left "

1) the minority isn't that small, some may even say it's the majority thought that's debatable because,
2) the majority on the left distance themselves silently and tacitly endorse the tactics of the minority through their quiet because they then get the result they want and can pretend "oh, that's not me, that's just a fringe group".

Basically, all the "white patriarchy privilege" memes but in actual practice.