''As a personal note, I do not like this decision. To me LFS is about learning how a system works. Understanding the boot process is a big part of that. systemd is about 1678 "C" files plus many data files. System V is "22" C files plus about 50 short bash scripts and data files. Yes, systemd provides a lot of capabilities, but we will be losing some things I consider important.
However, the decision needs to be made.''
Systemd, by construction, is a set of Unix-replacing daemons. An ideal embedded system setup is kernel, systemd, and the containers it runs (even without podman). This makes sense, especially given the Red Hat's line of business, but it has little relation to the Unix design, or to learning how to do things from scratch.
Neither does systemd its init.
Unknowledgeable people keep confusing systemd the init and systemd the daemon / utility suite. You can use just the init system without pulling in resolved or networkd or whatever.
Systemd is the Unix philosophy of lots of modularity. But because all the systemd daemons come from the same shop, you get a lot of creature comforts if you use them together. Nothing bad about that.
That's how vendor lock-in works, in which a myth is propagated that having it all come from under one roof is best. In fact, it is a guarantee that best-of-breed alternative solutions cannot be used. Interoperability is thwarted. This is why sensible Unix admins historically knew to keep options open for mixed-vendor sourcing as long as the bosses didn't get roped in to a single vendor or source.