We're talking about network stacks and network drivers, not web browsers. Migrating the network stack from the kernel to a user-land process is not going to measurably slow down web browsers, especially on modern systems with gigabytes of RAM, multiple cores, IOMMUs and whatnots.
> These are memory bugs, so the introduction of Rust into the kernel could help us here potentially, no need for an architectural revolution.
That would require rewriting the network stack and network drivers in Rust (driver code is much more likely to have bugs than the rest of the kernel) for this to be effective, otherwise you'll still have a lot of C code in the network path. I'd argue that this would be a bigger architectural revolution than porting the existing code and running it in user-land. MINIX3 went through such a change when drivers were removed from the kernel (can't find the publication about it right now) and they only required reasonably small changes when porting these to user-land, there were not rewritten from scratch.
But this is not just about memory safety, Rust code can still be vulnerable in many other ways (memory leaks, unsafe blocks, wrong assumptions, incorrect algorithm implementation, buggy/compromised toolchains...). Code running inside the trusted computing base of a system is a liability, enforcing privilege separation and principle of least authority reduces it.
