My opinion is different. Format standardisation is important, the main reason being lens coverage.
Lens are often the most expensive part of our purchase, and they are always optimised for specific image circle. We don't want our lenses to be obsolete with a new format in town.
My preference of shooting MF is actually not much to do with image quality, but viewfinder. For me, viewfinder is defining in image making process, it isolate and concentrate your focus, and large optical viewfinder is not replaceable. Secondly, I also like the fact that most MF has a very limited but definitive lens line, about 7-8 lenses for the whole line and most of them of stellar quality. For any 35mm system, there must be about 1 millions compatible lens, and that does nothing good for my OCD.
There should be a different in quality from 35mm to MF though, because what ever advances they make in 35mm, that can be applied into MF with additional advantage of bigger photo wells, lenses do not have to resolve tiny pixel pitches etc ... The reason its not as clear cut as it should be, is because MF manufacturers are tiny in comparison with 35mm's, with limited R&D and shrinking market.