But expressing opinions, especially controverse ones, should be made under ones own name. Posting anonymous to avoid loss of a few xp is a form of cowardness.
Do you have any evidence that this is actually happening here, or are you simply assuming that is the case? You may be right, and I don't particularly want to get into a protracted discussion about this, but you may also be wrong. People post as Anonymous for different reasons, and cowardice is not the only one I can think of.
Update: I see that defending Anonymous Monk is becoming less and less popular around here. That's a real shame.