As semiconductor technology advances, increasing miniaturization and integration become normal and expected. I imagine that in the 70s and early 80s, some people thought that the only "real" computers were minicomputers such as those made by DEC, or even mainframes. Highly integrated computers such as the Apple Silicon Macs are the logical continuation of the trend that began with the first microcomputers.

Having said that, the desktop form factor has its place. My next PC will be a desktop. But it will also be a Windows PC. I wish there was a Windows PC that had the same level of integration, and performance per watt, as the M1 Mac mini.