My post was comparing the current system that allows millisecond scale trading with a hypothetical one that slows trades down to something on the order of minutes. Your observation that people are willing to pay to exploit information asymmetries in the current framework doesn't address the question of how my proposed change would affect net economic value.
The metric of measurement is wealth, which profits create.
Your proposed change would reduce the benefit because it would eliminate the profit (wealth) that HFT firms create.
Your proposed system is not hypothetical; it is how all trades used to happen. HFT did not arise from nothing. People developed it because it created new profit in addition to that generated by slower trading.
My post was comparing the current system that allows millisecond scale trading with a hypothetical one that slows trades down to something on the order of minutes. Your observation that people are willing to pay to exploit information asymmetries in the current framework doesn't address the question of how my proposed change would affect net economic value.