Interesting article. I have not been paying attention. I would not have thought of this, but once you read it, it makes sense
QuoteWhile SLR lenses had some benefits over the rangefinder concept, they were optically inferior on the wide end and suffered from poor manual focus accuracy.
Also more camera shake since you have to move a lot more mass every time you click the shutter. There are, of course, ways around it. For long exposures, you move the mirror, wait for it to stabilize, then open the shutter. But it's a lot of complexity for little benefit with an electronic viewfinder available now.