As for Linux from Scratch - This is something that's been on my radar, but without the part I'm truly interested in (learning more about SysV) then I'm less inclined to bother. I don't buy the reason of Gnome/KDE - isn't LfS all about the basics of the distro than building a fully fledged system? If it's the foundation for the other courses, but it still feels weak that it's so guided by a future GUI requirement for systemd when it's talking about building web servers and the like in a 500Mb or less as the motivation.
OpenRC recently added user "units" aka services running as a user after a session start. Something that many new GUI user space applications rely on for various things.
There are growing pains. https://bugs.gentoo.org/936123
Especially when upstream hard requires systemd. More annoying when there's no real reason for it.
But there is a way forward and I highly recommend people try to build software to work without systemd before assuming it's always there.