There were massive improvements to performance in some of the areas criticized by PyCA and haproxy. X.509 handling will also be faster in the average case, with more improvements planned for 4.2.
See https://openssl2026.sched.com/event/2VSQR/performance-the-li... and its slides https://2026.openssl-conference.org/slides/2026-d3-1400-perf.... Recording should also be available soon-ish.