Still doesn’t align with the original assertion that dark matter “deniers” assert that interaction with gravity requires interaction with EM.
Currently I would group the “dark matter” into 3 camps, dark matter as a new form particles, dark matter as a combination of any sort of existing particles and matter e.g. wimps, primordial blackholes, brown dwarfs, cold baryonic matter etc. and dark matter as modified gravity this is MOND and TEVES et al.
None of which as far as I know make a statement around having to have interaction with EM if you are interacting with gravity.
