I don't fully buy those reasons for Michael's struggles.
In his last seasons he had some dreadful luck in the first races - but in the second half of the championship he was better than Rosberg - the car was just nowhere.
The team he joined thought F1 was going to be cheap. It took years of convincing Mercedes to invest, and then they fully focused (rightly) on the new rules.
Michael struggled (but it's not like he was seconds off the pace) to adapt his driving style to blown diffusers, he used to ride the throttle to balance the rear under braking and that was impeding the ebd - he was being asked a lot of times by his race engineer to stop touching the throttle under braking. F1 was just very different from 2006...and Rosberg was no pushover