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A bad viewfinder is a bad viewfinder and that has nothing to do with it being an EVF or OVF.
Agree completely.
... I don't know how folks use an APS DSLR, which explains the enthusiasm for live view. I love the viewfinder on my Mamiya 6 and, while I had it, a Horseman SW612.
Some of the smaller format DSLRs have good optical reflex viewfinders, but most of the inexpensive ones are terrible. The optical reflex viewfinder of a top notch pro SLR is one of the biggest factors in the price premium.
ANY Medium Format SLR has a huge advantage in the quality of its reflex viewfinder based simply on the size of the format and the amount of light coming through based on the focusing screen as an illumination source. (An SLR's viewfinder is essentially a dedicated peephole view of a back-projection imaging system with prisms to provide correct orientation.) Smaller format SLRs always struggle with the amount of light available and the quality of the optics used to provide the peephole view ... losses in the system degrade the image quality, the brightness, etc, and the modern trend towards lots of information overlays reduces it further.
Oh for simplicity! When I pick up my Nikon F plain prism body, the viewfinder is so delightful with a simple A or E screen installed. Just as it was with the Pentax 645 and, nearly, with the Olympus E-5.
But I prefer the even simpler optical tunnel for its brightness and zero blackout. Where it loses out is in accuracy of framing ...
They're all good in some ways and all fail at some tasks.