I'm not an OpenBSD user but it sounds like this changed recently in OpenBSD-land as well, because the "Will multiple processors help?" FAQ entry disappeared some time between January and March 2023: https://web.archive.org/web/20230112170731/https://www.openb...
I didn’t know this but it makes sense. Either way for most of the use cases (homelabs on residential internet speeds) either FBSD or OpenBSD’s PF will perform just swimmingly.
[1] https://man.freebsd.org/cgi/man.cgi?query=pf&apropos=0&sekti...