&gt; HFT mocks the true essence of trading<p>HFT is the true essence of trading--predicting short-term changes in supply and demand and acting accordingly.<p>&gt; This used to give us a real picture of the public sentiment for those companies or commodities.<p>Can you pinpoint some moment when it stopped?<p>&gt; Stocks are bought and sold in micro seconds<p>Most HFT strategies don&#x27;t actually do this. Buying and selling in such a short period implies a pure arbitrage, of which there are very few. The ones that do exist are generally fully exploited by the single fastest participant.<p>&gt; creating an unsustainable and unlevel playing field for the real humans in markets.<p>Depends on your investment horizon. The statement is nonsense for all but the shortest timeframes. In particular, the fundamental finance guys (the &quot;investors&quot;) are in no danger from the machines.<p>&gt; The current ecosystem is just unsustainable.<p>Why? Automated market-makers are a middle-man that temporally bridge supply and demand between &quot;real&quot; buyers and sellers. Kind of like a grocery store temporally bridges supply and demand between consumers and farmers. Kind of like a car dealer temporally bridges supply and demand between consumers and manufacturers. Kind of like... you get the idea. Why are equity markets different?