That's because the veneration of the BVM is exceptionally unique - if not outright defining - of Catholicism. Are Catholics known to come to the defense when something vile has been posted here about Joseph Smith or Alexander Campbell?
Why would we?? I'm ignorant of who Campbell even IS?
You understanding of Catholicism is sorely deficient. The word "ignorant" is fitting but cannot be appropriately applied on this forum.
Are Catholics known to come to the defense when something vile has been posted here about Joseph Smith or Alexander Campbell?
I really don't know since I can't recall something vile being posted about them. But I suspect not since Joseph Smith and Alexander Campbell are uniquely associated with specific denominations. However, the BVM is the Mother of Jesus and is common to all who are Christians. The Mother of Jesus should be respected by all Christians, but rather there are those "Christians" who do just the opposite.