Here's my take:
The video game industry started slowly and clumsily with the first and second generations, then burst into the modern age with the third generation. The industry peaked during the fourth, fifth, and sixth generations, and then entered into a decadent period during the seventh. The eighth, so far, has continued the negative aspects of the seventh.
So, while I agree the seventh was a step down from the sixth, and that it began in earnest many of the cynical business practices and game design problems that define modern video games, I think it's far from the worst. A handful of great games like Super Mario Galaxy, BioShock, Demon's Souls, and Xenoblade Chronicles save it from that title.