The Linux kernel scheduler has been accidentally hardcoded to a maximum of 8 cores for the past 15 years and nobody noticed
thehftguy.com
TL;DR This doesn’t mean that the scheduler can’t use more than 8 cores. The scheduler controls how to allocate tasks to available cores. How to schedule particular workloads efficiently…

I’m not smart enough to verify the accuracy of this claim, nor exactly what the implications are, but it seems like it might improve performance if fixed.