Harmful according to whom? It's safe to assume people don't support ideas they think are harmful to themselves and society.
What irks me is that the "ideology is intrinsically bad" idea is historically firmly part of conservative ideology. One early formulation is Burke's criticism of the french revolution.
I think pointing this out is not relativism.
You think murder is morally wrong. You think some govt policy is so important that when govt kills people while it is carrying out the policy, the ends justify the means. Ideology is what killed those people.
Maybe, but I certainly can't reduce my thinking about ideology to considering an example featuring comic villains.
I left it vague so people of both sides could relate to how it fits the other side's hypocrisy. But I suppose this also allows people who are looking for a fight to imagine that it fits their own hypocrisy and get defensive.