Abstract class instantiation not detected when decorated by a generic method that returns type[T]

[AzideCupric]

Describe the bug
When a class inherits from a Protocol or ABC that has abstract members and is decorated by a generic instance method that is a bound method of a generic class D[T].d(cls: type[T]) -> type[T], pyright fails to detect that the resulting class is still abstract and can be instantiated. The same abstract‑instantiation check works correctly when the decorator is a generic method on a plain class E.e[T](cls: type[T]) -> type[T].

Code or Screenshots

from abc import abstractmethod
from typing import Protocol

class A(Protocol):
    a: str

    @abstractmethod
    def test(self) -> None: ...

class D[T]:
    def d(self, cls: type[T]) -> type[T]:
        return cls

class E:
    def e[T](self, cls: type[T]) -> type[T]:
        return cls

d: D[A] = D()
e: E = E()

@d.d
class B1(A):
    pass

@e.e
class B2(A):
    pass

_ = B1()  # pyright does NOT report an error (expected: cannot instantiate abstract class)
_ = B2()  # pyright correctly reports: 'Abstract class "B2" cannot be instantiated'

VS Code extension or command-line
I'm using the pyright playground. The issue is reproducible there.

• pyright version: 1.1.409