why not religionism ?

[Angrboda]

Religionism sounds like a neologism.  If I heard it on the street, I wouldn't intuitively draw a parallel between it and agism or ableism.  I'd stick to better recognized terms.

But IS there a recognized term for discrimination against religion? ‘Religion discrimination’ is kind of clumsy, and (as has been pointed out) ‘xenophobia’ is just too broad.

Boru

Let's put it this way, is atheism the irrational prejudice against atheists? I think the term has more potential for confusion as it's not at all clear whether it's pro or con.

Maybe that's just unfamiliarity, I don't know.