Kernel bypass is not going to be something that is necessary on the client (even though there is a trend towards symmetric 10G internet becoming available in the US today, and according to Neilsen's law, it should be widely available within 10 years).
Still, I think bandwidth and latency should not be confused as it is on this thread.
From my experience, the Linux network stack is not bandwidth bound _at all_. I've used it extensively on 94gpbs infiniband networks without any issues. Problems arise only when you close up to line rate, meaning very small payload and low packet latency, which I think (though I'm not a game developer by any mean) is unlikely to happen in game use cases.
As for the technological side of things, I have my reserves that open source solutions like XDP, Netmap, or BSD BPF are able to compete with proprietary solutions like DPDK (which IMHO is more complete) or SF OnLoad - which is just an LD_PRELOAD on top of your existing BSD socket server.
> according to Neilsen's law
If were being honest, this is more of a fun fact than a law... We're talking about a single guy fitting a linear regression of a dozen points of his internet connection speed over time.
To the experts in the field in question these comments are usually incorrect and often highly amusing, but they are stated with such gravitas and certainty by the poster, that a casual reader might mistake them for the truth.
Also: https://www.mobygames.com/person/68015/glenn-fiedler/
Note that MobyGames is wildly incomplete.