SysVinit has been seen by some people in the post-systemd world as some sort of mystifying mashup concocted by sadists, yet I've found that when it is explained well, it is clear and human-friendly, with easy uptake by newcomers. I echo that this decision is a pity.

It’s not just explaining but whether you have to support it on more than one distribution/version or handle edge cases. For a simple learning exercise, it can be easier to start with but even in the 90s it was notably behind, say, Windows NT 3 in a lot of ways which matter.

"When it's explained well" is the keyword

I'm not a systemD fan but SysV is not without its quirks and weirdness and foot guns