Yes, but skewed how? What would the observable effects be? It can't be anything too drastic, as we don't observe sudden, extreme shifts in the properties of incoming light. The issue is that our current model is remarkably well supported with very little evidence to point to where it may be inaccurate. For example, the redshift and the angular size of galaxies follow each other fairly closely. We don't find galaxies with high redshift that are also very large (angular size). The highest redshift comes from galaxies which are barely larger than a handful of pixels. Nor do we find sudden shifts in the light when we move our observations between galaxies or clusters into the voids between them. In fact, the CMB can be seen when looking through these galaxies, and there is no known association between the placement of these galaxies, clusters, and voids and a change in the CMB as far as I am aware. If the permittivity and permeability of space changes over time or distance, it changes in such a way as to make it look extraordinarily similar to the expanding universe that the standard cosmological model represents.