Most prop trading firms arent public. Rentec have something like $150bn under management and are making 20-40%/yr return. If they had a public "market cap", they'd be huge
Medallion makes those returns and is capped at 10bn. The rest is more traditional fund management (and performance isn’t great).
Also from what I understand Medallion is HFT in one sense (fast trading with short hold times) but not to the point proper firms are where being fastest is necessary for edge.
