China has made great improvement over the last several years in raising the living standard of it's citizens. Not surprising a survey would show satisfaction. By contrast, moving from the sad state of affairs during the cultural revolution to the present day situation certainly makes things look quite rosy. Most western nation survey's show people are dissatisfied with the direction of their countries. The level of satisfaction one has is based on where one was to where they are now. There can be no denying the lives of most Chinese citizens are much better than in the recent past and are perceived as improving in the future.
As with all surveys, the mix of those participating is often a determining factor in the outcome. Found another link that indicates the survey did not include many Chinese who would be less than satisfied.
"In the survey, conducted over the last 10 days of May
in major Chinese mainland cities,"
To Chinese people, future looks bright
Had the survey covered people from the rural communities, the result would likely show a lesser level of satisfaction and hope for the future.
China still has many challenges they need to address but I believe China will make improvements needed to become a major world player in more areas than just economics in the near future. If their many thousand year history is any indicator, with the right leadership, China can lead the world in innovation, economics, culture and societal advancement.