So what you actually mean is that the continuous tracking function of these mirrorless interchangeable cameras is not at the same level as that of DSLRs and as long as it is not at the same level, you consider them to be not functional at all.
Well, I have NX10, NX100, NEX5, GF2, EP 1/2 and E-PL2 and their continuous tracking do work (some brands better than others) even if they do not match that of DSLRs in efficiency. To me, that's not the same as '
contrast detection does not work with ANY MOVING object'.
Even with DSLRs, predictive tracking efficiency varies from brand to brand and I have tried them all...Canon, Nikon, Olympus, Panasonic, Sony... Even with the best, there would be situations where tracking would fail too. No DSLR can track every moving object 100% of the time.