How dare a system have "checks notes" have too much documentation describing how it works.
I think it actually shows a problem, which is that BSD is designed for all your machines to be special snowflakes with individual names, edited config files, etc instead of being mass managed declaratively. So you need to know how to do everything because you’re the one doing it.
Why is there a chapter on custom kernels under "common tasks" that assumes you're going to have a C compiler and kernel source on your machine and want to installkernel on that same machine?