The original trader still has the ability to capture his information rents in a single trade on one market. Nobody can see it and step away or react before the

The original trader still has the ability to capture his information rents in a single trade on one market. Nobody can see it and step away or react before the execution goes through. That's all anyone is guaranteed. HFTs face the same problem. If they're trying to cross the spread to put on a trade or hedge, they also have market impact costs and slippage. I think it's controversial because a lot of their marketing implies all HFTs do this as their primary business and thus add very little value. It creates this narrative of a parasitic activity that intermediates trades which would have already occurred where no risk is taken. I don't think that's the case in reality. All HFT strategies are looking at order books in the products they trade, and they definitely make money (or avoid losses) when someone executes inefficiently across exchanges, but there's more to it than that. HFTs are very successful in futures and non-US markets where products trade on a single exchange. How do they do that if they aren't good at predicting prices and taking risk?