Type narrowing fails on type(None) or NoneType

Bug Report

Type narrowing can't remove type(None) from a union.

To Reproduce

def get_class(x: int) -> type[str | None]:
    if x > 0:
        return str
    else:
        return type(None)


x = get_class(1)
if x is type(None):
    print("hi")
else:
    x("test") # Cannot instantiate type "Type[None]"

Expected Behavior

Type narrowing should eliminate that possibility. It works with None, but not NoneType.

Actual Behavior

Cannot instantiate type "Type[None]"

Your Environment

mypy 1.16.0
Python 3.12.10

Start with the provided Python reproduction and run it against mypy 1.16.0, comparing the type(None) case with the working None case. Done means the reported narrowing no longer leaves x as Type[None] in the else branch while preserving the existing behavior for None.