Do you have any book suggestions for learning modern C++ memory management techniques? I'm beginning to think maybe it's time to fill that gap in my programming knowledge.

Hmm, modern C++ memory management is not entirely different from before. You have std::unique_ptr which is a game changer. I recommend just learning the language itself well. The C++ Primer (latest edition) plus Effective Modern C++ would be a good start. Also, read that doc floating around about everything a programmer needs to know about memory.

Or arena allocation - which, by the way, is something I wish was more supported in mainstream languages