[Pharmakon]

That’s true, but it’s also true that hypothesis is preferred because of the abject failure or other theories and hypotheses to match those observations. The window for something other than DM is exceedingly narrow and only MOND has a hope of fitting through, and currently not in a form that’s very compelling.

[nonbel]

The point is this "window" isn't narrow at all once you allow dark matter.

Practically any theory plus 95% "dark matter" can match the data.