> shared_ptr is a much better solution for garbage collection. One I wish that java had implemented.

I'm pretty sure there is a large body of (computer science) research work around the topic of deterministic (reference-counted) vs non-deterministic (non-reference counted) garbage collection. There are lots of pros and cons for both sides. Also, I find it interesting that Java, C#, and GoLang all chose non-deterministic GC, but Perl and Python use deterministic GC. (I'm not sure what Ruby does.)

I think CPython does reference counting for its memory management, it still has to run a GC since reference counting does not handle reference cycles.