> while slower speed participants have an improved experience

Wall Street lobbies to ban HFT every few years, hoping people who don’t like how it looks will back them up.

Slower participants in equities are block traders. Folks moving hundreds of millions if not billions at a time. Large institutional investors. Dealers. Retail, on the other hand, would get hosed, though it would also become much more profitable to execute, so maybe that brings some service perks for larger retail traders.