I started building houses in 1972. It was not until I thrashed my back by being Mr. Macho (No problem. I can carry that 24-foot 6x12 up the ladder. You go get the burgers") that I went full time into shop work. At that point, the general quality of home building had already deteriorated significantly from what it had been even ten years prior.
I remember the first time we installed a fiberglass uni-tub shower enclosure. We literally had to build the walls around it because it would not have fit through any of the interior doorways. It came with an "unconditional one-year limited warranty;" whatever that is. But we were thinking, "One year? And we're building it into the house?"
The newest thing in siding was T 1-11, which I never figured out to mean anything other than plywood with grooves in it.
And that was only the beginning. At the same time, a parallel downward spiral was occurring in the furniture and cabinet industry. Since then the overall quality of houses and the furniture they contain has steadily declined. At this point, the stuff built in the '70s is pushing 40 years old. From what I can see, this stuff is not aging gracefully. While some of the furniture and casework was cheap enough to just toss when it breaks, much of it represents a big enough financial investment that repairing it is going to be the only good option.
We are going to need an army of fix-it guys. In our shop, we are getting more and more calls for repairs and with the economic situation being what it is, we are not hanging up on nearly as many of them.