Well, this particular change (PEP 563) is IMHO actually striving for improved static typing and better performance, so, I guess they're in sync with that.
-- PEP 649 would undo those performance improvements and possibilities of improved static typing over concerns of libraries that user types at runtime having to adapt (I took a look at the issues reported at pydantic and while the API would need to be adapted when PEP 563 would come into effect, I don't really see the major breakage they're talking about -- not that it doesn't take some work to adapt, but I don't see the reason it'd suddenly become impossible to do, it'd only make their own lives a bit easier over the performance cost of all the libraries that use typing without requiring runtime information).
-- PEP 649 would undo those performance improvements and possibilities of improved static typing over concerns of libraries that user types at runtime having to adapt (I took a look at the issues reported at pydantic and while the API would need to be adapted when PEP 563 would come into effect, I don't really see the major breakage they're talking about -- not that it doesn't take some work to adapt, but I don't see the reason it'd suddenly become impossible to do, it'd only make their own lives a bit easier over the performance cost of all the libraries that use typing without requiring runtime information).