> but the /r/murica used to be a joke about overzealous patriotism, then it became something... else

Maybe people did notice, and just decided to take this subreddit for something else than laughing at over-patriotism. It's a very successful strategy against shaming, if you can pull it off - just not being ashamed and not being afraid to demonstrate it. Reddit provides excellent venue for that, subreddits being good Schelling points.