Yeah, they spent a ton of effort trying to cram automatic-config-and-library-discovery-like features everywhere when they would've been MUCH better served by requiring explicit dependency injection... and then just adding DI wrappers externally. That's what contrib is for.

As it stands, due to the tower of abstractions that could've just been "init with an implementation of this interface", you need to learn several pieces and how they work together (hint: convoluted and horrifically inefficiently) to modify any piece, and inevitably you learn that to get what you want, you need to swap out a major portion of it... but doing that while maintaining the auto-registry nonsense is a gigantic effort. If it's even possible.

It is the new poster-child for "design by committee". It's horrific. Unfortunately it's also usually the best option in large setups. I greatly approve of the high level goal, but omfg