The incessant "small-format-camera-X is as good as medium format and more practical" - trend starts to get annoying!...
Why can’t people stop being obsessed with sensor quality (all modern sensors, at base iso, have good enough DR and resolution since years!), small camera weight differences and other non essential points.
Photographic quality / high-fidelity is about optics! and here: Size does matter!
For the rest, you could use your phone camera ... or a 35 mm DSLR for action photography.
Larger images (transmitted by a lens) will have better micro-contrast and maximum sharpness – before even being “sampled” by a sensor / film – than “equivalent” (dof and fov – wise) images on a smaller system!
On a larger format system the image produced by the lens is better to begin with : Larger size = shift to lower spatial frequencies = using the lens in a better zone of its Modulation Transfer Function = better overall micro-contrast = higher fidelity (to use an audio term) / lifelikeness.
You could say that between equivalent “images” produced by a lens on different format systems there are more “analogical details” / better analogical information in the larger image: "It's the MTF advantage, stupid"
No need to use extremely sharp lenses to get 25Mpx max of useful details like with a D800!
Why is there such low MF "defense" even here in an MF forum!?
Maybe it deserve to die? when even Phase-One CEO can only come up with "differentiation" as the main advantage for MF! (c.f. his ~recent video interview) ;-)
or maybe it just doesn't need to be defended?
I am not a professional, I'm just taking pictures for myself (and the people important to me); for the joy of stopping time into a lifelike image, and for that there is no volupty outside MF (or bigger)
p.s. small format trolls: visit small format forums ;-)