I don't see how it follows that they are admitting something by shrugging their shoulders. But what this is missing is that there are technical reasons for flat design, namely performance and power usage, that are critical on mobile devices.
Design based on function and performance removes emotions that contribute to the overall user experience. A purely engineering approach can lead to boring design, IMO.
I really don't understand the performance argument when we've been dealing with skeuo for some time. Of course, skeuo can be overdone, but in balance, it's what many users find useful.