> HFTs will probably find their own flavor of fraud given a few more years, if they haven't already.
This is what psychics call a "cold reading" - a statement that is bound to be true eventually! At some point in the future HFTs will "find" (?) something approximating fraud. That almost can't not be true. But I don't see how it relates to your statement that Jane Street's reported profits are fraudulent.
Sure, that statement is a bit of a non sequitur. Here's one that isn't:
Highly profitable, speculative, and complicated US financial firms have consistently grown to threaten the stability of US financial systems before collapsing. As such, these types of firms have a high burden of proof for legitimacy. If that hasn't been met, betting on fraudulence is pretty safe given historical context.
Fair. I disagree with "consistent". Some highly profitable, speculative, and complicated US financial firms have done this, but others haven't. E.g. insurance firms.
This is what psychics call a "cold reading" - a statement that is bound to be true eventually! At some point in the future HFTs will "find" (?) something approximating fraud. That almost can't not be true. But I don't see how it relates to your statement that Jane Street's reported profits are fraudulent.