It's a different kind of pain.
The entire "distribution" is cohesive and clean in a way that no Linux distribution manages. A lot of duplication of effort and ugliness is avoided.
But everyone develops for Linux, and you run into places where things don't work. And performance doesn't come close to Linux on the top end or even high middle end.
It's a mixed bag, a not so good benchmark:
https://senioradmin.de/BenchmarkBSDLinux.html
And a little better one (with FreeBSD13 but 14 is already out and it's much faster[1]):
There are presentation about how Netflix uses BSD for video delivery for its performance, so it can't be that bad.
The Playstation System software (Orbis OS) is a fork of FreeBSD:
https://en.wikipedia.org/wiki/PlayStation_4_system_software
I'd guess performance was pretty high on Sony's list of priorities.
The playstation runs freebsd rather than linux licensing reasons, not for speed.
And the bits that are most performance critical (primarily graphics) are very custom and likely have little in common with vanilla FreeBSD
So how well it performs for Sony says very little about how well it will perform for you - since your use cases have a high chance of being very different from theirs
you'd be surprised how many nice things we don't get because of licensing.
dumb example: magsafe. it'd be nice and cheap to have it on all laptops, but laptop manufacturers can't license it (because apple won't sell licenses) so they have to go with other routes.
> I'd guess performance was pretty high on Sony's list of priorities.
Do you consider the Playstation 4 hardware "top end"? I'm mostly thinking about SMP and IO performance.
See the geometric mean results here: https://www.phoronix.com/review/3990x-freebsd-bsd/5
"At 16 cores, RHEL8-based CentOS was about 17% faster than FreeBSD 12.1 while at 128 threads the lead expanded to 28% based upon the geometric mean or 21% when comparing the GCC9 results on FreeBSD 12.1."
It's my understanding that FreeBSD 13 has narrowed the gap a little bit. I was a total NetBSD fanboy at the beginning of my career, but was eventually forced to move away when Linux's momentum inexorably made running NetBSD (and FreeBSD) harder.