1. Read up on the seL4 microkernel. It pretty much destroyed the "microkernels are too slow" argument. 2. Modern day hardware is mostly just ringbuffers mapped

1. Read up on the seL4 microkernel. It pretty much destroyed the "microkernels are too slow" argument. 2. Modern day hardware is mostly just ringbuffers mapped to memory. There's a real convergence of hardware interfaces, virtio, and io_uring into all being this very similar looking thing. With IOMMUs, moving drivers to userspace is pretty attractive. There's not much of a difference between a cloud VM getting access to a VFIO device from the hypervisor and a userspace device driver getting access to hardware from the microkernel. And there's a lot of money in making cloud VM networking & storage faster.