Will President Biden Resign Prediction Market - Is Insider Trading Unfair?

President Biden has special knowledge of this, so he could just bet on the true outcome and make a lot of money unfairly. He could even change his behaviour, for example resigned in unexpected time, just to make more money. Is this unfair? One answer is that normal markets, for example the stock market, face these same problems, but manage them by making insider trading illegal. Another answer is that, while this is bad for other investors, it's not bad for the accuracy of prediction markets or their use in creating unbiased social consensus.