Attacking religious groups is perfectly fine, not bigoted and not comparable to bashing based on race, gender or sexual orientation. That's because religion is a chosen trait that one decides for themselves, unlike the other traits. Its more comparable to bashing and attacking members of a political party.
Um, no?
Um, yes? One can not change their race or sexual orientation. One can change their religion and political party.
Religion correlates heavily with culture and heritage, and is a deeply personal aspect of one's identity that carries connections with spirituality, family, and tradition. You're going to respond by saying it doesn't have anything to do with family and tradition for you. This response is irrelevant, because your experience with and attitude towards religion isn't really typical of most believers throughout human history and cannot be proffered as a template for such.
People throughout history have endured great suffering and even martyred themselves for faith. Just because it isn't an immutable factor, doesn't mean it's a random label that everyone simply adopts as they please.