Well, but the IGC is not contrarian without context.

It's an In Group Contrarian -- so contrarian in the context of the group.

This means that

(a) they are not just contrarian for the sake of it (then they would be contrarian to the ideas of every group, not just one)

(b) they are not opposed to everything the group believes (in that case they wouldn't be in-group contrarians, but mere ideological enemies of the group)

(c) they share some beliefs and core tenets of the group (hence the in-group qualifier)