Ok, before really reading this.
I understand Prager’s point, that all sin and, thus, are not “good”.
Putting aside that fact, I appreciate the rabbi’s thinking. I think the point there is that most people are good in the sense of not all-out evil. Most people are pretty regular. They can be made evil, they can give into evil and become so, but largely people are just going about their business.
That's why the path is so broad.
Matthew 7:13-14