I thought it was started by those who thought that some who question Islam were doing so in a disrespectful way.
The problem being that some see criticism of Islam as something we should not do because of any of the following
a) it was deemed un-Christian
b) it was seen as a continuation of oppression by Christians against non-Christians
c) it was seen as irrelevant, as nothing’s real any way - no religion has sole claim to the truth.
I believe that vigorously defending the truth is Christian. It’s not oppression because we’re only on an internet site and no one’s condemning people to death. And Christianity has the truth, Islam does not.