The meta answer is ... the theme of this puzzle. How meta is that?
So this meta is fairly convoluted and hard and the grid is hard but I expect the AHA moment will snap when it comes.
Fair warning: I had to rely an a lot of convoluted entries that go from the sublime to the ridiculous to the completely absurd. (Freebie: In other metas when you see a multi-word unusual entry it's usually a themer. Not here!)
And in hind-sight the grid should have been smaller. I have figured out how to have a few long entries without forcing myself to have a lot of long entries. As a result the themers are sparsely distributed.