Yes, but many of these are testable. Thus for example, Oscar's hypothesis that "Things are only tropes if they happen more often in fiction that in reality, so to detect them you need an accurate map" is testable. You could take a random sample of people who edit TVtropes and test their map accuracy in completely separate areas (say things that can be often estimated with a Fermi calculation) and compare that to a general sample of people. Oscar's hypothesis suggests that the Tropers will do better.
RobinZ's point is difficult to test, but presumably if one examined in detail what pages have historically stuck around and which have been merged or deleted, one could get data that would test it.
I would also consider my thesis undermined were it demonstrated that the rate of rationally-insightful contributions to TV Tropes was significantly higher than for other notable Wikis (e.g. Wikiversity).
This is our monthly thread for collecting these little gems and pearls of wisdom, rationality-related quotes you've seen recently, or had stored in your quotesfile for ages, and which might be handy to link to in one of our discussions.