Can't you say that about virtually anything? I'm sure having, say, MIDI synthesizers in the kernel would improve performance too, but not many think that is a good idea.
Depends on the workload and scale. There are cases where offloading everything to userspace in order to minimize context switches into kernel space would improve performance, as well.
Depends on the workload and scale. There are cases where offloading everything to userspace in order to minimize context switches into kernel space would improve performance, as well.