I love how you're getting downvoted for stating basic facts. 3 people in America own more wealth than bottom 50% of the population. Similar situation in Canada where fewer than 90 the richest families own more wealth than 3 provinces combined.

https://www.forbes.com/sites/noahkirsch/2017/11/09/the-3-ric...

https://globalnews.ca/news/4360299/wealth-inequality-canada/

The concentration of power, in this case, refers to political power not market(economic) power. If you think about it carefully, economic power often is very weak and vulnerable as they often derive them from consumers which means they can only maintain it by giving consumers what they want. People like Bezos, Bill Gates are far less powerful than say, Putin, Erdogan, Xi, etc.

As an example, how far did Bloomberg's billions take him in the democratic nomination?

In what way does capitalism act to prevent concentration of political power, then?

Towards the end of the video he also calls up 1900s America as the period of time that best exemplifies capitalism, not surprisingly an era marked by extreme inequality.