Is be interested to know some of the examples and rationale behind each. Not because I want to dispute but just out of curiosity.
I don't have any side-by-side examples but the final image difference between formats is due to working distance, tonal range, lens design and DOF.
Take a ~75-90mm lens on a 6x7 camera which is a "normal" vs. a 50mm lens on a 35mm camera. The longer focal length has inherently less depth of field BUT due to a lesser enlargement factor to get the same size print, the COC of the medium format image works in your favor and the apparent DOF in the final print widens just a little bit.
If you crop out exactly 24x36mm in the center of a medium format frame the medium format lens' focal length is exactly the same as the 35mm lens' focal length
with regard to the final print. A lens is a lens though and it doesn't know or care what it is projecting light upon so the DOF is a rigid constant with regard to focal length, regardless of format. It is the reproduction ratio, final enlargement and viewing distance which lend a difference to DOF
Now, the 6x7 is a tighter crop being closer to 4:5 ratio while the 35mm is a 2:3 ratio so a 6x9 camera is a better comparison for non-cropped final images but most miniature format folks doing printing are cropping the 35mm frame to suit the 8x10 paper and so the 6x7 medium format comparison is completely relevant.
Your working distance with a 6x7 camera is usually greater than a 35mm camera. Now, the eminent Mamiya RB and RZ 67 cameras kind of set the bar for this format in SLR use because there are so many of them, they are inexpensive (now) and the lenses are fantastic. The reason I bring this system up is that the camera has a built-in macro bellows so you can get much closer.
That system aside, shooting a medium format camera up close is rather like shooting a rangefinder up close as they tend to have longer close-focus working distances with standard lenses. This distance affects the DOF far more than final print enlargement ratio so that ~75-90mm lens on the medium format camera tends to settle back down closer to the drawing characteristics of a 50mm lens in 35mm format.
In spite of that the medium format system tends to draw a little more "three dimensionally" due to the longer focal length lenses ability to more selectively focus at natural looking apertures. This is why a lot of folks didn't (and still don't) like APS sized sensors. One the wide angle side, the DOF is about the same shooting a 28mm lens for example, but the angle of view is much closer to a normal lens.
Then there's tonal range. The medium format lenses tend to be much older, mature designs that draw with a very long tonal range and allow the shooter to tailor the image more than a very modern, higher contrast formulation. This and the fact that the sheer surface area of the medium format film allows tonality that is hard to get out of 35mm frames.
Ok, I'm just rambling now. Geeking out on lens design and format.
Phil Forrest