The main difference between ideologies and religions is, in my view, principally in the way that the former masquerade their metaphysical beliefs, instead of declaring them explicitly, in order to misrepresent themselves as commonsensical or even scientific.

Perhaps the metaphysical beliefs aren't that much important. They are almost always free-floating, not tied in any significant way to expectations and experiences, and serve as a group identification sign. (After all, it doesn't seem to me that, say, Rand's Objectivism is less explicit with its assumptions than Zoroastrianism. That ideologies don't refer to gods doesn't imply that they masquerade their basic beliefs.) Putting too much attention to these beliefs is itself a mistake, since it diverts attention from the real mechanisms of harm, which are related to biases and shared among ideologies and religions.