I never claimed otherwise - that was the point I was making when I said that absolute IQ was not the only key issue, and everything was somewhere along a continuum that traded off IQ vs. size and portability of the system.

In particular, I believe that nowadays, the best mirrorless cameras are basically equivalent to crop-sensor DSLRs on IQ, and superior to them in terms of overall portability - especially when the full suite of lenses is also considered. They won't be better in IQ than full frame DSLRs, any more than full frame DSLRs will be better than much larger sensor cameras like high end MF digital gear. But most folks don't need that last bit of IQ at the expense of the added bulk (and dollars) and that will always be the case.