Not a "bloated, monolithic system"?

But so does faulty layering and a lack of code reuse.

SysV init does not cover functionality that is essential for every init system, so there are countless reimplementations of this functionality; usually in shell script. Most of them with severe bugs.

The prime example is process management. There is at least one implementation per distribution - usually that one is mostly OK, since it had a decade or more to mature. But then there are countless implementations by upstream developers and those often are a nightmare (they were usually written as an afterthought by developers who had no experience whatsoever in that area).
It gets even worse once you look at typical "inhouse" development. I have seen things called "init scripts", written by - otherwise capable - Java developers, that I wish I could unsee. Those creations have caused real damage.
Also, those scripts are rarely portable to other shells or non-GNU userspaces. Worst case, they won't even fail noisily but simply no longer work correctly in specific circumstances.

Systemd's larger core functionality and declarative syntax are a huge improvement. Things that should have been easy from the very beginning finally are.