Not always! There has always been crappy construction, done with an eye toward profit rather than quality, just as there have always been customers who want (or need) quantity over quality. I used to spend time in a lovely little house near the beach that had the second floor framed with 2x4 joists on 24" centers. The joists were also notched for the grooved lath that held the house wiring. The second floor was like trampoline! If they hadn't been relatively straight-grained virgin Douglas fir they probably wouldn't have lasted a year.
When my parents bought their latest house the kitchen had been remodeled with custom-built cabinets. They were pretty ugly, looking like they were built of oak flooring. Guess what? The kitchen was remodeled by a flooring contractor! At any rate, when my folks ripped out the old kitchen, they found that the slightly-springy second floor was supported by 4x4's on 4-foot centers! Not only that, when my dad was tearing out the old wallboard he found three live electrical wires that had been merely cut off and left to hang inside the walls. Now that's attention to quality.
I have rehabbed a fair amount of old furniture, and I know that you know that there is a lot of very poor craftsmanship behind those drawer fronts and under the upholstery, and very cheap materials.
I think your safety glasses are getting a little too rosy. People are people. Some like their jobs, are good at them, and care about the results. Some customers know good work and are willing to pay for it. But there are just as many people, and maybe more, that only care about short-term profits, are only punching the clock, need something right now at a low price, are only going to use it for a little while and get rid of it, etc.
If you look around, you'll find that actually, housing today may not be as charming as in the past, but in general is much safer and more energy-efficient. Also, in general, buildings today are not meant to last forever, so why invest excessive amounts of labor and materials in them? If the customers decide at some point that keeping buidlings around is better than always ripping down and rebuilding, then the "old ways" may come back, at least in terms of high-quality craftsmanship and materials.
But don't hold your breath.