True, but we have a kernel networking stack with a certain interface and a rich feature set. The kernel cannot break that API. In contrast, a new userspace sta

True, but we have a kernel networking stack with a certain interface and a rich feature set. The kernel cannot break that API. In contrast, a new userspace stack doesn't need to worry about backwards compatibility or supporting every use case. So yes, the kernel can do just as good, but it's harder.