Hegelian dialectics was possibly sublated by marx, but Marx’s dialectic is not a dialectic idea but a material world which does exist as a basic assumption that is perfect for any theory which intends to be useful. You cannot sublate the material world itself. But again, I think that you are under the impression that, because you thought of a quick gotcha, that this hasn’t already been thought about and written by many scholars before you. Hegel himself saw this gotcha coming