"io_uring had a maximum throughput of 5.0 Gbit/s "

Wut? More than 10 years ago, a cheap beige box could saturated a 1Gbps link with a kernel as it came from e.g. Debian w/o special tuning. A somewhat more expensive box could get a good share of a 10Gbps link (using Jumbo frames), so these new results are, er, somewhat underwhelming.