Another daemon for managing control groups

You're not being specific, you're just answering one question. Where is the specification for every software available on Debian? Where are the multiple implementations for every software?

I was asking why *everything must* be implemented multiple times.

Also your answer implies that systemd has a specification which it is being written against. I'm not aware of such specification. Systemd did create various specifications.

Suggest thinking about my question a little bit more.