I also think that Warren is dead wrong. The internet/FB/GOOGL allow smaller businesses to flourish. 15 years ago, only major brands could afford to advertise or reach an audience, now niche companies can exist with a national or international presence.
If anything, these tech monopolies hurt the previously established, Coke/Kraft/Sears and they hurt VC's who can't find a way to scale a niche brand with smaller TAM's or compete directly with Amazon, etc.