#3 Compatibility especially with network and virtual machine stacks are becoming so much more important. Going ARM will relegate Apple to just a "toy" and nothing more.
They've
announced that it is going to have virtualisation support and that Docker (for a start) will run.
Linux is already far in advance of either Windows or MacOS on ARM and most of the major server-side applications already build for ARM64. Most server-side development work is CPU independent anyway. For Docker, you just need to build ARM versions of the binary images you use (if they're not already published) from source - and the Docker equivalent of "universal binaries" is already a thing:
https://www.docker.com/blog/multi-arch-build-and-images-the-simple-way/ - and with all the interest in ARM servers at the moment, it's something that developers need to get into anyway.
...meanwhile, if you really must virtualise x86, for server-side
development purposes, you're probably not going to notice if your virtual stack is running under emulation.
Or, you can just spin up a VM - of whatever architecture that you need - and make an
exact clone of your production server to work on, with a nice fat pipe to the interwebs (where most of your source material probably lives) .
(If you're hosting
production servers or doing stress-testing on Mac hardware - when Apple don't make any server hardware - then you're already holding it wrong).