One place where I prefer dict() is where dicts are used as "nested kwargs", e.g. in Django's ORM for passing default values.

    User.objects.get_or_create(
      username="bob",
      defaults=dict(
        email="bob@example.com",
      )

this makes it easy to move fields between `defaults` and `kwargs`. Granted, you could achieve the same isomorphism with ** operator, but less readably IMO.