Historically, the mods have not killed a post for discussing Hacker News meta, although on occasion they apply a penalty to meta submissions. (the original post only had 32 upvotes, which is enough to get swallowed)
Presenting the facts out of context isn't helpful. The original post might have "only had 32 upvotes" but, as mentioned in this article, it received about 20 in less than an hour. More than enough to get to the front page, where it was steadily receiving more upvotes until it just vanished. The post was not "swallowed".
When a story gets to the front page more people will see it and some may upvote it. Likewise more people will see it and some may flag it. I'd hypothesize that longer term or more active users are among the people who are more likely to use flags. Likewise, I suspect that long term and active users are more likely to not want to see meta posts on the front page.
The point is that the post wasn't swallowed in the usual sense. We now know that the original post fell drastically because it was being flagged by users.
Indeed, HN recently allowed a post that advocated gaming the system because it encouraged debate: https://news.ycombinator.com/item?id=13676362
A conspiracy theory, even backed by data, is not the best application of Occam's Razor.