@jym- The reason is a number of things. Part of the answer is that things like vacuum cleaners were made out of strong components, and as a result were worth fixing, because they would last. A lot of what was made back then had motors that were metal, the plastics they used were pretty strong, and more importantly, the motor in a vacuum could be taken apart so you could replace the brushes, these days they are all one piece units pretty much,nothing to replace. Then, too, everything these days is controlled by circuit boards, and when they go there often is no replacement available, or if it is, it is really expensive. Washing machines used to be driven by belts, which could be replaced with little work, and the motors in the washing machine were beasts that could be fixed, too. The controls were basically clockwork mechanisms, that could be fixed or replaced pretty cheaply. These days washing machines use direct drive mechanisms that are often made out of plastic, and to replace would take a lot of labor and if you got it repaired, would cost a fortune. The circuit boards that drive them are expensive as well, and replacing them is a fortune.
The other side of it is many things comparatively are cheaper then we grew up. When I was growing up, a 19" color tv was a pretty expensive deal, around 400 bucks in 1970’s dollars, you can get a high def set for 400 bucks in today’s dollars. If you tried to get that repaired out of warranty, likely it would cost you a lot more than a new one would, so people just throw them out.
There is some irony to all that, cars are the exact opposite. Back when I was growing up, the typical car owner didn’t keep cars that long (and please, don’t tell me stories of cars your family kept running, my family was like that too, we fixed our own cars, and kept them running until they literally died), back then the average car was kept somewhere around 5 years or so, these days that number is well into double digits. A lot of people would trade in cars every couple of years, or would get a new one when the financing on the old one had finished (or often, dealers would ‘pay off’ the old loan, by including the pay off value in the cost of the new car,they still do that with leases and such). Part of the reason was cars were relatively cheap in one sense, the typical car in the early 1970s was around 2500 bucks or so, and even with inflation adjustments, it is still less than typical cars today adjusted to today’s dollars. However, people did that in part because despite what I get from some people, about how cars back then were a golden age, etc, they weren’t. Back then, for one thing, unless you lived in California or Arizona or the like, cars rusted out, you would routinely see cars with leprosy of rust after a couple of years, you don’t see that any more. Engines and drive trains back then, when you got to 30 or 40,000 miles, were considered ready for a total rebuild, these days 250,000 miles is the expected length they are expected to last, they are totally different. Cars are more expensive, but partially because they are expensive, and partially because they for the most part are infinitely more reliable then the cars of 40 years ago, it is worth fixing them. Appliances these days like washing machines and dryers have a useful life until the warranty runs out, cheaper units like coffee makers last a couple of years if you are lucky, cars can run for many years with only basic maintenance.