It is more moonshot to design an API while Linux devs are constantly pulling the rug under.
Microkernels provide nice secure API boundaries and optimizations to reduce performance impact when crossing them on modern CPUs.
The monolithic design forces you to stay in either user or kernel mode as much as possible to not lose performance. Adding the API and ABI incompatibility makes it near impossible to maintain.
It will require a hard fork of Linux, which won't be Linux anymore. Monolithic design is the artifact of low-register-count CPUs of the past. If you are going to create a hard fork of a kernel, why not use a more modern design anyway?
If you get your driver into the mainline kernel, it gets maintained. If your driver is not in mainline, then you have to deal yourself with kernel internals changing.
Hell, a while back one of the kernel devs was actively screaming for hardware manufacturers to reach out to them so folks could work with the manufacturer to get drivers for their products into mainline. There was even a website and nice instructions on what to do and who to contact... but I'll be fucked if I can find it anymore.
There's nothing nefarious going on... it's explicitly stated (and well-known) that the stable interface to Linux is the userspace interface. Inside the kernel, things are subject to change at any time. Don't want to have to work to keep up? Get your driver into mainline!
Microkernels provide nice secure API boundaries and optimizations to reduce performance impact when crossing them on modern CPUs.
The monolithic design forces you to stay in either user or kernel mode as much as possible to not lose performance. Adding the API and ABI incompatibility makes it near impossible to maintain.
It will require a hard fork of Linux, which won't be Linux anymore. Monolithic design is the artifact of low-register-count CPUs of the past. If you are going to create a hard fork of a kernel, why not use a more modern design anyway?