Depends a bit on how widespread they are.
Pockets of apparent non-conformity imply there is something locally different there, perhaps a concentration of rare but real AsYetUnknownium. Which does not invalidate what we think we know, just widens the error bars on it a bit sometimes someplace. For TBD but probably small values of “bit”, “sometimes”, and “someplace”.
Conversely, widespread non-conformity from existing expectations, like the surprise following the discovery of the CMB, pretty well says there’s something significant, if not fundamental, missing from the current theory. So the “bit” part may be small in magnitude, but the “sometimes” and “someplace” turn into “everywhere” and “always” as far as we can tell so far.
Ref the two articles, if indeed we discover that the gravity equations need a few new terms to account for dark matter, but at very large scales dark matter is, on average, evenly distributed, the effect on much of cosmology will be a bit like the effects near-c velocities have on mass and time versus normal earth-bound engineering. IOW very significant in the very high speed corner of the envelope, and a rounding error in 99.9% of it.
At the particular scale where dark matter anisotropies matter, it will matter a LOT. But that scale is neither whole universe, nor whole Solar system. It’s somewhere in between.