Saying that something is not a systemd replacement because it does not do x feature that systemd does misses the point that systemd does too much. /sbin/init can be simple, and written in any language, and when it is, its often better than systemd because of that.
If software supports start but not stop or restart or enable disable as both systemV and systemd do, its still a fully functional systemd replacement if your context does not need those features