By investing regularly in an index fund, an investor who knows nothing can outperform most professionals. When dumb money admits it is dumb, it stops being dumb.
For most investors, institutional or individual, the best way to own stocks is to hold a lowest-cost index fund. Those who follow that path will, after fees and costs, end up ahead of the vast majority of professionals.
Very low-cost index funds are extraordinarily friendly to investors. For most people, they are the best choice there is.