They're designed to cover a lot of different processor types. Servers have different needs to microcontrollers. Nevertheless you would expect code that works on the microcontroller, to scale up and work on the server so there is some value.

You probably don't need to same code to run on such differing hardware though. The value is in your code working on 2 processors with optional FPUs.

I don't think you're ever going to get to USB levels of plug and play, but you don't really need that.

Edit: So yes you might get usb 3/c/whatever levels of confusion, but you don't swap processors multiple times a day so not really a problem.