It brings Linux closer to Windows in philosophy. Systemd is building a coherent large codebase (albeit modular) that solves all the problems, as opposed to Linux userspaces old philosophy of having a collection of "expert" tools, where each tool or project did one thing, one thing only, and did it really well. Then the system was a collection of such expert tools.

The collection of expert tools naturally aren't as well-integrated with each other, so on a system level the solution might look a bit spotty. But every function is thought through and works really well. Plus, each tool is useful on its own, which makes the system very configurable, introspectable, and hackable.

The "one big codebase that solves all problems" approach might appear more stable all-in-all, but it's a fundamentally different approach where you no longer have a bunch of expert tools, but rather a large collection of mediocre software components who's only real purpose is to be integrated with each other.