Answer by A Quora admin:
Everyone gets to say it. In my opinion, no one gets to be right about it.
I understand why religious people are perpetually trying to disown some who self-identify as members of their religion. They're fighting not to be tarred with the same brush, or they're looking for reasons to exclude others, or they fervently believe in the objective truth of their religion. As an irreligious person, I don't have a stake in any of that. I use religious labels descriptively, not prescriptively. If lots of people who believe X self-identify as followers of Islam, then Islam is a religion that includes X. It may also include not-X, of course, if lots of self-identified Muslims believe not-X.