Thank goodness someone posted this link to Roger Cicala's post.
It strongly questions the dogma that "sensors are out-resolving lenses". The resolution limits of each format remain uncertain at this stage. It is possible to determine what the reasonable resolution limits of each format are, but that would be a very costly experiment to run.
As for the business of diffraction degrading optics down to a certain f stop these figures get quoted more like dogma rather than science. Never are the mathematical calculations (along with the justification of implicit assumptions used in the calculations) shown so that others can double-check how the f stop limit of usability was derived. Instead, all you get is an f stop number quoted at you like the number "42" given as the meaning of life in
The Hitchhiker's Guide to the Galaxy. Even if the theoretical calculations were to be shown (so that they can be independently verified), they are still hypothetical and speculative in nature. You still need to run the empirical experiment proving that the degradation from diffraction is significant.
I also agree with Roger Cicala about the DxO Mark stuff about perceptual megapixels being nonsense ("those of you who believe in perceptual megapixels or that the earth is flat" Roger and out). DxO Mark has never published an externally verifiable methodology for how they measure this, once again making the numbers they post no better than the
ex machina assertion that the meaning of life is "42".