Templated symbol names are gigantic. This can impact program link and load times significantly in addition to the inflated binary size.

Duplication of identical code for every type, for example the methods of std::vector<int> and std::vector<unsigned int> should compile to the same instructions. There are linker flags that allow some deduplication but those have their own drawbacks, another trick is to actively use void pointers for code parts that do not need to know the type, allowing them to be reused behind a type safe template based API.