Ubuntu is experimenting with making a more modern CPU build: https://discourse.ubuntu.com/t/trying-out-ubuntu-23-04-on-x8... https://www.phoronix.com/review/ubuntu-x86-64-v3-benchmark

Also -O3: https://www.phoronix.com/news/Ubuntu-Evaluating-O3-Optimized

I am not sure off hand how that CPU level compares to Intel Clear Linux's options. The phoronix comparison fo Ubuntu with and without v3 were mostly quite small single digit percent though, on an Intel CPU.

Notes: Canonical (Ubuntu) is my employer, I am not working on this project.