Isn't industrial diamond use already a lot higher than jewelry use? It seems unlikely that consumers switching to lab-grown would "drive volume up and prices down" in any meaningful way - except perhaps for the jewelry grade stones themselves.

That includes stuff like diamond grit. You don’t care about the color or clarity of grit. Tenth of a carat on up? You care about that for jewelry use. And that translates into better non-grit industrial diamonds as well.