The problem there is that stuff in space is very evenly distributed, so that sort of super-clumpiness is hard to sell. There would need to be a mechanism for w

The problem there is that stuff in space is very evenly distributed, so that sort of super-clumpiness is hard to sell. There would need to be a mechanism for why, in our observable universe, there happened to be no antimatter. If we saw other cosmic-scale clumpiness it might be a clue, but the differences are all tiny.