Presented without context, for amusement purposes only, a page from my notes:

	FreeBSD	NetBSD	Linux
Per-process default route	Poorly documented, possibly incomplete	Probably not	Poorly documented, buggy
Can compile PhantomJS	Probably	Probably	Yes
Jails	Yes	No	Not really
Xen paravirtual guest	Incomplete	Yes	Yes
System call tracing	truss	None?	strace
pipe2	Yes	Yes	Yes
closefrom	Yes	Yes	No
sysctl	Yes	Yes	No
getauxval	No	No	Yes
signalfd	No	No	Yes
execvpe	No	Yes	Yes
Reference documentation	Acceptable (YMMV1)	Acceptable (YMMV)	Major gaps
Tutorial documentation	Terrible	Terrible	Terrible
Package management	Broken as designed	Broken as designed	Good
System maintenance automation	I can’t find any	I can’t find any	Acceptable
QA reputation	Excellent	Good	Good
Security reputation	Good	Good	Debatable
Development community	Unknown to me	Unknown to me	Full of assholes

¹ It makes sense to me, but then, I taught myself Unix system programming and administration by reading the SunOS 4 manpages.

https://www.owlfolio.org/possibly-useful/os-for-project-x-2015/