I wouldn't necessarily say this is related to the economy (The economy has other issues), but more related to our culture. Our entire culture is focused around consuming, buying the next thing, having the nicest stuff, etc. Heck our high schools even teach us how to properly consume, and how to acquire things we cannot afford.

However in life you will have to pass up some things you want in order to maintain living within your means, as a result you are going against the constant consuming behavior that our culture has taught us, and feel a failure for not buying all that stuff.

I couldn't speak to the social pressures of the past (I didn't live through them). My personal experience is that when I was able to ignore the consuming pressure society gives, the amount of stress and pressure plummet and I have been able to enjoy life much to a higher standard.

Those middle managers may be in that sweet spot of enough to be comfortable and feel successful, but not so successful they feel the need to compete with the consuming elite of execs and millionaires. Don't be fooled though, there are plenty of people in other "class brackets" that are able to shed the stress and pressure of the US culture.