Saying that next billionairs are 20s and 30s guys is simply something that happens since decades.
Warren Buffet created a new dimension for investments and many other less famous surely followed the same route.
The same within communication method and lean management/process optimization.
Billionaires start always from their 20s. So we are just agreeing that people in their 20s or 30s are more efficient in exploiting newer business methods and strategies. Let's keep learning from them.