No, its not the end of the world. And I agree, LFS isn't going to be the best resource for learning how a compiler works or cron or ntp. But the init process & systemd is so core to linux. I can certainly see the argument that they should be part of the "from scratch" parts.

You still build it from scratch (meaning you compile from source).. they don't dive into Linux code internals either.

They still explain what an init system is for and how to use it.