> It speeds up market corrections, increases liquidity, and means buyers and sellers get quicker execution closer to consensus market value.

This is the BS that Wall St says whenever people complain about them doing it. Nobody actually benefits from getting their liquidity in 8ms instead of 8.2ms, and in fact it costs them the money the high frequency trader was making compared to having the exchange's computers do it without taking a margin for itself.

> If financiers and doctors are wealthier, they have more disposable income, some of which they will spend in retail, benefiting retail clerks.

Or they'll further outbid the people in retail on things like housing, making them poorer yet.

> They will also get taxed more, benefiting other tax payers.

Only if the other taxpayers actually get taxed less instead of the government giving the extra money to cronies.