Starting with release 12.0, FreeBSD has a working SO_REUSEPORT implementation, so with the release of 20.7 this has become available to us.
Within unbound, it is possible to use this option. I have enabled 'so-reuseport: yes' in the unbound config, and found it beneficial, mainly in providing better distribution of the load between the threads/CPUs.
Please try it for yourself, and maybe one day it could make its way into the unbound default settings.
Thanks, I'm deploying this at the office to see how it behaves. Reminder ticket here:
https://github.com/opnsense/core/issues/4303
Cheers,
Franco