Honestly "Dark matter is also believed to interact with ordinary matter in ways other than gravitational." is wishful thinking. Why? We have no a priori reason to believe that matter must have multimodal interactions, and there is potentially a real ontological crisis. If dark matter only interacts gravitationally - which even people who don't "believe in dm" must accept is a possibility, them dark matter is unfalsifiable, so we have to be ok with the possibility that there is something in the universe that exists but we cannot ever satisfactorily argue that it does. LCDM advocates know that they are on philosophically shakier ground if that's the case, but aren't brave enough to admit it because they are afraid it weakens their main cause by association (to be fair it does, we should probably be exploring other explanations first)