> How can we make use of that silicon in scenarios like that?

Well, in theory you could run them simultaneously. Use one of them for compute and one of them for display. Of course, this may well be quite a stretch in practice; GPU compute in any consumer software is completely nonexistent, to a first approximation. But it's worth thinking about, as there has been a steady stream of research coming out for years about various useful things that you can do with GPU compute.