Earlier quoted context omitted.
[...] since the whole userland that you need is included in the binary (worth noting) you just dont get the debugging stuff (which is okay as long as you can choose)
would argue that it's not just the userland. you only have the functionality you need and your bits. for example an http server would have the http stack + your app. there is no userland, there are no drivers, just your app as the only thing that is running on the machine. your app basically merges with the "kernel"
the kernel has the drivers you need. the http stack needs libc or equivalent. basically its the same except statically linked, and without debug/troubleshooting tools.
yes, really!
it does reduce the attack surface/amount of things.