This is true. But even if just 5-10% of the population is DIFM, that's enough to fund a lot of companies and take the growth away from a lot of mature companie

This is true. But even if just 5-10% of the population is DIFM, that's enough to fund a lot of companies and take the growth away from a lot of mature companies. With interest rates low, a mature company can get away with 3-4% profit growth. Drop their topline revenue 5-10%, and their profit drops much more than that.