In 13 years of digital, I've used Canon 1Ds Mark lll (21Mp), Hasselblad H3Dll 39ms (multi-shot), Sony RX 100 Mark I, Canon 5DMk IV.
In terms of colour straight out of the box, the Hassie blows the others clean out of the water. (I do a lot of art repro)
In terms of the "elasticity" of the file - dynamic range and (in particular) how the file behaves in Curves, I rank them as follows:
Hassie
Canon 1Ds MkIV
Sony RX 100
....and a distant fourth...
Canon 5DMk IV
My point is this:
39MP on a sensor the size of the Hassie is nothing, and you can see it in the files. It's like looking at Fuji Velvia of old.
Squeezing more and more pixels onto the same size sensors hasn't worked for me with my most recent purchase - the 5D MkIV.
Dynamic ranger and colour just aren't there compared to the other cameras, although looked at in isolation, the Canon files are fine.
I haven't tried the new Nikon (a lot of pixels on the same size sensor) and I've heard great reports about the Sony A7r iii ("Medium format is dead", etc.) but, I think that something fundamental needs to happen with sensor technology before we make serious progress. A total redesign from the ground up.
D.