Looks like the author is into game development, and STL is often avoided in that context. I think one of the reasons is performance - STL has made some design decisions which prioritise general use over performance.

Often cited example is `std::unordered_map`, whose spec necessitates an implementation using separate chaining (or similar). Depending on the use case, in high performance applications, a different implementation can be much faster.

Although I don't understand why some people hate all of STL so much. Like sure, use your custom hash map, makes sense. But is anyone really replacing basics like `std::find` or `std::sort`?