So you believe that retail investors benefit from the fact that HFT’s can trade in the nanoseconds after 4:00 but retail investors cannot?
Please pass what you are smoking.
What you mention of taking advantage milliseconds after the close is not true. The market moves as fast as a human being can process the information in a earnings report. And i can guarantee you its not in milliseconds or nanoseconds or seconds. And even then you wont be able to predict what the particular underlying will do.
The stock market is 50/50 proposition... actually to be correct its a 53/47 proposition. Look up price efficiency models and black schoels