>There were other choices that Linux could have taken rather than sysvinit vs init.d
I don't think that is true. If you look at those other distros you'll mostly find that it either didn't pan out, or it's quickly approaching the same design and architecture of systemd, where distros start using declarative prgramming to integrate tooling around common workflows. This is inevitable when you consider the constraints on the system as a whole. Other related service management tools like Docker are under the same constraints and you'll notice those have a similar architecture too.
I don't think that is true. If you look at those other distros you'll mostly find that it either didn't pan out, or it's quickly approaching the same design and architecture of systemd, where distros start using declarative prgramming to integrate tooling around common workflows. This is inevitable when you consider the constraints on the system as a whole. Other related service management tools like Docker are under the same constraints and you'll notice those have a similar architecture too.