If you un-comment the print_exc() call, you'll see that it still fails - for queue.Queue:

Manager failure (for Queue)
Traceback (most recent call last):
  File "fish.py", line 74, in main
    add_type_in_own_process(mgr, type_name)
  File "fish.py", line 61, in add_type_in_own_process
    use_manager(obj, type_name, mgr=mgr)
  File "fish.py", line 35, in use_manager
    obj.append(getattr(mgr, type_name)())
  File "<string>", line 2, in append
  File "/usr/lib/python3.8/multiprocessing/managers.py", line 850, in _callmethod
    raise convert_to_error(kind, result)
multiprocessing.managers.RemoteError: 
---------------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/lib/python3.8/multiprocessing/managers.py", line 243, in serve_client
    request = recv()
  File "/usr/lib/python3.8/multiprocessing/connection.py", line 251, in recv
    return _ForkingPickler.loads(buf.getbuffer())
  File "/usr/lib/python3.8/multiprocessing/managers.py", line 959, in RebuildProxy
    return func(token, serializer, incref=incref, **kwds)
TypeError: AutoProxy() got an unexpected keyword argument 'manager_owned'
---------------------------------------------------------------------------