The "popular" reaction places this issue at the level of "Christianity versus the rest".  In point of fact, Christianity itself is so much fragmented into different sects that it is sometimes even difficult to rationalise that they have anything in common at all (many other faiths share the same problem).  At times, in considering immigration applications, the NP government (itself strongly Calvinist-oriented) found Roman Catholicism and atheism equally repugnant.
It could perhaps be questioned whether studies of comparative religion have any place in schools below the senior high school levels.  Are the younger children sufficiently mature to derive any benefit from them?