None of this negates the fact that the spatial frequency resolution plots for the lenses, or lenses+sensor combined system would adequately describe these facet

None of this negates the fact that the spatial frequency resolution plots for the lenses, or lenses+sensor combined system would adequately describe these facets under discussion. So what if a manufacturer with their 4X monochromatic pixels that really only constitute just X color pixels, but insinuates the 4X numbers to be the full color pixel count? The spatial angular frequency plots of the compound lens(es)+sensor would quickly become the "figure of merit" to check regarding these facets. Of course nothing would prevent them from stating lies and providing false plots, but then any laboratory could start underwriting (measuring and publishing) such resolution specifications.