The article mentions that may just be the amount the SEC can actually prove.

> Overall, Robinhood’s investors may not have been harmed by their decision. The SEC identified $34 million that Robinhood customers lost by not receiving best execution, which is much less than the money they saved by forgoing trading commissions. (That said, their losses might also be much higher. That $34 million comes only from “certain” transactions, which might be the tip of the iceberg that the SEC possessed the ability to measure.) They were, however, duped.