Warren Buffett and Charlie Munger have been openly critical of the Robinhood trading app which, according to a recent article in CityWire, raises “some bigger questions that must be faced by all investors,” particularly those in the ETF space.

The article argues that many Robinhood investors “do not conform to the options-crazy, GameStop-obsessed day trader” approach but rather run “fairly convention ETF-heavy strategies involving broadly diversified portfolios.” It adds that they also use a “hybrid” investment approach that involves creating “satellite” portfolios that include single stocks (mostly in the tech sector). Such an approach points to a wider market trend: “a thirst for access to fast-growing, disruptive private businesses.” It also points to a failing of the ETF industry to provide a structure that can offer “passive exposure to private equity and venture capital.”

According to the article, the satellite approach also underscores the rise of momentum strategies, “another profound shift which Buffett and Munger might be missing.” It notes, “In the good old days of share trading, there was huge friction dragging down returns from a momentum-based strategy—namely, trading costs. As technology has improved, these frictions are now ebbing away, and running a simplistic momentum-chasing strategy is becoming ever simpler to implement even for private investors.”

Those investors “brought up on the classics of investment theory might need to rethink our way of screening through a universe of thousands of stocks,” the article concludes, adding that “fundamentals-based narratives, such as those that prevail Buffett and Munger’s worldview, might increasingly be irrelevant” and “ETF investors using apps like Robinhood might just be heralds of a new investment normal.”