Perhaps you're right and that was the "peak" of the middle class. But I suspect we have a long way to go. Wealth will be concentrated among a small number of people (as it mostly is today anyway), and the rest of us will be back serving as low-paid and low-class servants, farmers, lumberjacks, boatmen and milkmen. If we're lucky.
Time to watch Masterpiece Theatre and brush up on my hat-tipping and groveling.

Seriously though, I agree that the loss of high-paying, blue collar jobs overseas has already hurt the middle class, but I also suspect that high-paying, white collar jobs, like mine, are going to be scarcer in a post-peak world.

Study with an expert and watch Anthony Hopkins in Remains of the Day!

With less energy supporting our society, we will lose a layer or two of complexity in our economy, and complexity is what gave rise to the populous white-collar class.

I'm already experiencing what this will be like myself. I'm a former globe-trotting, big city corporate communications manager now living in rural Vermont. It's quite a change. A lot of the people around here are very self-sufficient, and get by on very little compared to city and suburban folks.