[bradleyjg]

My point is that, at least in the US, the post World War II economy was unusual and the factors that lead to it are unlikely to ever be repeated.

We are reverting to the status quo ante about what middle class means.

[solosoyokaze]

I agree with the first part of your comment but there wasn’t really a middle class prior to the 20th century.

The petite bourgeoisie would probably be considered upper-middle class today. Even the industrial revolution was only a small period of humanity.