I thought adding type hints would improve the execution speed. If not now, at some point. Apparently they are not even considering it. They consider speculative specialization, which is likely more work than specialization based on known type hints. Still great to see that 'speed' is not ignored by the developers.
Though personally I would dislike this, since every time somebody mentioned about type hints they commented on the property of them not causing 'ANY RUNTIME EFFECTS'. Of course the specializations come with guards, so if the annotation is wrong it is just going to work as a mispredicted option and fallback to the generic implementation though the concept of them changing the initial layer of optimizations is not something that I'd rather see in 'the Python language. PEP 563 even moves this properties forward and renders them totally uneffective in the eyes of the interpreter.