even when using the same kernel (5.11-rc3) and kernel config and the same gcc (10.02) with same flags on the same machine,
Fedora 33 WS finishes any code compilation 10% to 25% faster than Ubuntu 20.10.

Kernel Compilation: 126min vs 143min (user)
CERN ROOT compilation: 177min vs 224min (user)

Out of pure scientific curiosity:
What is the reason for that massive difference?
(Test machine: ryzen 2700x, 16GB, nvme)