Aliasing of `Tuple` in the way you've suggested probably won't be possible any time soon. This would require additional work in type checkers because `Tuple` is handled as a very specialized case in the code today. This would also require us to update the `tuple` class definition in builtins.pyi so it is parameterized by a TupleTypeVar. Currently, it is not, and we may need to wait for all Python type checkers to support PEP 646 before we can do this. Given that some of the major type checkers still haven't added support for Python 3.9 PEPs (604, 612, 613, 614) it could be a long time before PEP 646 is universally supported.
-- Eric Traut Contributor to Pyright & Pylance Microsoft Corp.