The median American simply does not earn $48k/year with one salary.

If you take into consideration your quality of life, it's probably better than a lot of medieval (and even more recent) royals. A car replaces a horse drawn carriage which required a driver, stable staff, etc. You can get meals delivered from restaurants for minimal cost. You have access to a massive variety of foods from around the world. Fresh fruit, veg, and meat is easily affordable. You have a machine to wash your dirty dishes. You have a machine to wash your clothing.

You have access to nearly every piece of human knowledge on demand for almost no cost. You can communicate with anyone, anywhere in the world, at any time, for virtually no cost. You have access to more sources of entertainment than you could consume in a lifetime, at a very low cost. In your pocket you carry a super computer with a multi-core processor, high resolution display, solid state storage measured in gigabytes, with voice and touch interface, that can access all these things over a wireless high speed internet connection.

Every person living in a developed country is living a lifestyle that would have required many servants in any other era. People are just spoiled, greedy, entitled shits. They have no appreciation for how good their lives are. They have no comprehension of the complexity of the underlying systems that make their lives so incredibly easy. And yet they always want MORE.