I understand what you are saying. Belief is close to identity as is ethnicity or race or sexual preference or gender. In general we wouldn't attack someone for being a specific race, gender, or sexual preference; we also wouldn't tolerate stereotyping on those grounds.
When it comes to ethnicity it's a little more complex - for example, the American South has a pretty distinct culture. Some elements associated with Southern identity are positive, others are negative. While people at DU are pretty comfortable stereotyping American Southerners, would they feel the same way about Italian American communities or Latino communities? Probably less so. And while Culture is a general learned set of opinions and attitudes, and thus subject to change, most would accept that cultures and ethnicities have both positive and negative traits - so people would be encouraged to dump the negative traits while embracing the positive traits of whatever culture/ethnicity they come from.
I agree with the formulation that belief in whatever faith you participate in is akin to love - but I don't think that will be understandable or acceptable to those anti-Theists on this board. To them, since belief is a foolish affectation to begin with, you should drop it entirely, or at least join a faith that they approve of a bit more. They literally don't understand why a person would choose to be religious except in the most shallow of terms, and as such there will always be a gap.
Bryant