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Can you expand more on #5?

It seems that having some galaxies without dark matter is also pretty bad for CDM. Why would CDM be absent in those cases? Without an explanation, isn't it bad for CDM (as well as MOND)?

Nobody wants a theory where exceptions can be hand-waved away as "Oh, that galaxy must not have DM" or "That galaxy has too much/too little/different balance/etc".

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Right. MOND has one tuning parameter, but effectively CDM has infinite tuning parameters, and (worse) they can be tuned on a case-by-case basis.

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What the article above posits, that dark matter could be stripped out from a galaxy after a collision.

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Right, I read that as a possible explanation, but that's not the root explanation.

Roughly, my question is "Don't we see other post-collision galaxies that still have dark matter, and if so, why?"

If we have two identical scenarios with different outcomes under a theory, that doesn't bode well for the theory.

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