Do not report using indirectly deprecated aliases.

mypy/checker.py

@@ -293,19 +293,11 @@ class InstanceDeprecatedVisitor(TypeTraverserVisitor):
     def __init__(self, typechecker: TypeChecker, context: Context) -> None:
         self.typechecker = typechecker
         self.context = context
-        self.seen_aliases: set[TypeAliasType] = set()
 
     def visit_instance(self, t: Instance) -> None:
         super().visit_instance(t)
         self.typechecker.check_deprecated(t.type, self.context)
 
-    def visit_type_alias_type(self, t: TypeAliasType) -> None:
-        super().visit_type_alias_type(t)
-        if t not in self.seen_aliases:
-            self.seen_aliases.add(t)
-            if ((alias := t.alias) is not None) and ((target := alias.target) is not None):
-                target.accept(self)
-
 
 class TypeChecker(NodeVisitor[None], CheckerPluginInterface):
     """Mypy type checker.

test-data/unit/check-deprecated.test

@@ -103,7 +103,7 @@ def h() -> None: ...
 [case testDeprecatedClass]
 
 from typing import Callable, List, Optional, Tuple, Union
-from typing_extensions import deprecated, TypeAlias
+from typing_extensions import deprecated, TypeAlias, TypeVar
 
 @deprecated("use C2 instead")
 class C: ...
@@ -141,11 +141,13 @@ x8: List[Optional[Tuple[Union[List[C], int]]]]  # N: class __main__.C is depreca
 x9: Callable[[int], C]  # N: class __main__.C is deprecated: use C2 instead
 x10: Callable[[int, C, int], int]  # N: class __main__.C is deprecated: use C2 instead
 
+T = TypeVar("T")
 A1: TypeAlias = Optional[C]  # ToDo
-x11: A1  # N: class __main__.C is deprecated: use C2 instead
-
+x11: A1
 A2: TypeAlias = List[Union[A2, C]]  # ToDo
-x12: A2  # N: class __main__.C is deprecated: use C2 instead
+x12: A2
+A3: TypeAlias = List[Optional[T]]
+x13: A3[C]  # N: class __main__.C is deprecated: use C2 instead
 
 [builtins fixtures/tuple.pyi]