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.
Think about it, you can't obligate the systemd folks to maintain codebases that aren't theirs.. would be madness.