For me its all about diminishing returns IMO. The benefits of minimizing latency from a day to hours to minutes does exist but the benefit gets smaller as the window reduces (and costs more to achieve). It also depends on what you believe the purpose of the market is - to scalp and trade, or to own a piece of an asset. If your in the latter category then anything tbh lower than a second provides little social utility. I have worked for these firms in the past and while they believe they do make the market "efficient" it's really the profit motive/bonuses that drives their behavior. What they are really after is "edge" to make more profit at the end of the day IMO, and one source of edge is information asymmetry which being faster than competitors gives you.