Kevin O'Leary recommends buying only dividend yielding stocks, what are arguments against this?

https://www.youtube.com/watch?v=9PMkgtwMkxc

In several interviews Kevin O'Leary recommends buying dividend yielding stocks and keeping no more than 5% in a single stock name and no more than 20% in a single sector (with regular rebalancing).

What are arguments against this?

I know that Jack Bogle and Warren Buffett both recommend indices for normies, but indices do not comply with these rules.

What are your thoughts?