I'm not sure what to make of that statement either. It is like saying running a linter on your code makes it slower. It just doesn't make any sense. If the aut

I'm not sure what to make of that statement either. It is like saying running a linter on your code makes it slower. It just doesn't make any sense. If the author argued that annotations made the code slower… maybe. CPython exposes them on, e.g., __annotations__, so, conceivably that would slow down function creation and consume more memory, but my guess would be it would be such a tiny difference that would be vastly outweighed by the benefits of having annotations.