... and here we go again
. Don't you think that full frame mirrorless doesn't have to be a small camera? I mean, why should it be? "Compact large aperture AF zooms" ...
Size reduction has thus far been the key selling point of all mirrorless systems, it doesnt mean the camera needs to be tiny like the NEX but I'd guessing most potential users wouldnt want something much larger than an M9.
Yes, M9 is big enough, but I would like a better grip.
why would you need such lens for a mirrorless camera?
For exactly the same reasons you'd want one on a DSLR.
Is there any non-FF mirrorless system which has such lens to offer?
It makes no sense. Just buy a DSLR if you want it all balanced.
..and if the the vast majority of users do deside they want that balance and get a DSLR instead such a mirrorless system is not going to be very sucessful is it?
I'm just pointing out that a FF mirrorless is a much riskier move than an ASPC one because it would be unable to target an existing large market with a smaller system. The majority of ASPC users are happy with an already small kit zoom lens and maybe a small fast prime and/or a slowish tele zoom. FF users on the other hand have gotten used to many larger lenses that are going to be more difficult to balance with a smaller mirrorless system.
and the vast majority of users are using crop DSLRs for telephoto because getting the same reach with FF camera would be too big, too heavy, too expensive.
You are right, FF mirrorless is not for everybody, just like any FF DSLR. However, I think that it would be very successful.