The meta-strategies help market prices be accurate, faster, by beginning to move prices towards the “right” number in advance of information that would do the same thing. In the long run they don’t misinform.
This obviously excludes strategies based on fraud, misinforming the public, etc.
Accurate or right here means economically efficient, not correct according to the prediction of some simplified model. Such strategies very much obfuscate any attempt to find and measure causal links between particular events and stock price movements.
I could say the markets are up due to the vaccine news, or because the US election was called and people are seeking stability, or because the US election was called and the market prefers biden, or because investors are pricing in a Trump 2024 run, or because people just expected it to go up after any of those things, or because a collection of automated trading bots saw some arcane pattern in the data which has no real-world relevancy but they nevertheless have been trained to buy. None of those predictions are falsifiable.
Correct; the prices are based on the sum of all information, which is a list we do not have. And “the market” is of course a basket of individual prices, which are not measured the same by everyone.
This obviously excludes strategies based on fraud, misinforming the public, etc.