It's not about making sense economically it's just that there are not many ARM platforms out there, so if you want a native ARM dev box, Apple is pretty much the only choice.
That's not true at all. There's plenty of ARM platforms out there, especially in the Linux world they've been around a long time (does the Raspberry PI ring any bells? Or Nvidia Jetson? Or Freescale iMX6? Or Beaglebone Black?). Of course, they don't have M1 performance, but best in class performance was not a condition in you statement.