I very much respect the work that you did compiling all the results, however I cannot help but wonder if you started a chicken and the egg situation.
He's not responsible for people who misinterpret or misuse that data, though. And while it's hard to support a counterfactual in a situation like this, I imagine there would still be a lot of netdeckers and metagame watchers even if MJ wasn't aggregating tournament results--they'd just be less well-informed about metagames outside their own.
And so enter the meta tracker that was the regionals results thread. I know there are a lot of casual players that did not read that thread. I know every competitive player has that thread on follow. After every regional, casual Xwing night at my LGS would see at least one person running a clone of the first place or runner up of the most recent regional tournament.
It's worth noting--again, because I say this a lot--that these people are Doing It Wrong. The aggregate tourney results are not a menu from which to choose your next build, but rather a set of things you should make sure your build (whatever it is, and wherever it comes from) can address.
So the question remains, does the meta exist because its real, or is the meta in and of itself meta? Does telling people what the meta is make them take a meta list, or do they take a meta list because of the actual meta? And is there a distinction?...
Granted there are some ships that are more powerful than others, but the regional meta thread demonstrates cycles of group think and circular reasoning.
So I agree that it's an interesting question, and I think aggregating tournament results as MJ does here is absolutely having an effect on the metagame.
But shift your perspective a bit, and it becomes a much less meaningful question. Instead of a metagame, maybe we should be talking about an ecology of X-wing, or (to be somewhat more esoteric about it) a fitness landscape. In any case, however, that landscape exists regardless of whether and how well players are informed about the landscape; that knowledge affects its shape, but not its fabric.
Some ships really are more powerful than others, or at least better suited to a particular role or niche, and players are going to make decisions on some basis about which ships are likely to perform best. If that basis is less heterogeneous by geographical location that it would be without MJ's threads, or if it has become informed by knowledge that's broader in scope than it would otherwise be... that's something of a moot question, I think, because not only is that counterfactual difficult to establish but it's not the universe we're living in now.