Think of the PC/Laptop as a Car.
The CPU is the Engine.
There are a good few people who still like to tinker with the engine. Even if today it is just getting the EMS Remapped.
So move to the PC and replacing the CPU with a more modern one is like replacing the old 100bhp engine with one from the GT version that output 110bhp.
MS is akin to Ford/GM/whoever making it impossible to put the 110bhp engine into a car that left the factory with the 100bhp engine fitted by changing the engine mounting points and other stuff.
That has to be the worst attempt an an analogy ever.
If the CPU is the engine, then surely trying to put a newer CPU on an old motherboard would be closer to installing a new engine, and that's almost never possible because processors switch to different sockets, or support different chipsets and memory every couple of years. Last time I checked, Microsoft don't make generic processors or motherboards, so exactly what this story has to do with them I'm not sure.
As for engine mounting points, there is no standard for these things at all, so there are thousands of combinations of engine and chassis that would never work in the first place.