As a traditionalist who believes in the importance, righteousness and and benefits of traditional values and in the existence of GOD, i'm not bothered about dawkins being denied being able to speak because he represents militant athiests who are intolerant of religion, religious people, and people believing in GOD. They constantly are trying to prove GOD doesn't exist and mocking, insulting and disrespecting people who beleive in GOD and their religious values and beleifs. So in this respect leftists can be used as useful idiots against another strain of leftism.
But this does not take away from the hypocritcal, devious and selective opposition reasons why the left did this and always does this, which is that dawkins specifically said things which muslims found offensive, if it was any other religion that he said the same thing about then leftists would not have done this because for them only muslims are among their victim groups which they have to be sjw's for and appease, because leftists want to use muslims for their own rotten leftist agenda even if muslims don't support their leftist ideology, since muslims some how in their minds fit into their leftist narrative.