Reducing theological perspectives to judeo-christian views is also very narrow.

That said, focusing on some narrow topic is also totally legitimate, as human being we can’t encompass everything and the rest in our tight attention window.

Well, fear of being labeled retarded leverage on common mechanisms with fear of missing out which is one of the main engine for religious groups (or any social group really). Or said otherwise, people tend to want to be accepted in the group and will consider how to not be rejected.

Only when looking at "other" groups one generally starts to activate critical thoughts on the down sides of being part of that group.

A name in western culture is often not even chosen by the carrier, so any concern about what could be attached to the name is already part of this wanna show group value adhesion.

Religion is ultimately for a great part a matter of identity and they sure don't think of themselves as retards.

People think it's doctrine, scripture and proseltysing that sustains it and anyone looking into those first 2 at least would think they're idiots but mostly it's things like CREDs (credibility enhancing displays) and group ties that contribute to believers selfidentity which calcifies the belief.

Looking at their or a different religion for what it is would challenge their sense of self and as humans we really don't like that kind of cognitive dissonance.