I can say this from personal experience and observation. I have worked with millionaires and lived with the poorest of poor. All those that I have seen with money, desire more and power. They are never satisfied, always worried about losing what they have, trying to achieve more, and usually very unhappy in relationships. And often put themselves above others as if to be admired or worshiped. More than often, not taking time to consider God, much less seek his wisdom.
The majority of the poor I have known, try to help one another and strangers, with what little they may have. Always sharing and caring with others, even with strangers. Rich in family life and love. Joyful in the Lord and trusting in him.
This is not to imply that one set or the other is inherently evil or wrong. Just what I have seen and known to be the case, the majority of the time. Spending so much time chasing money and materialistic things, does not leave much time to look around, see God, or thirst for his desires. Much less to take the time to be still as God tells us we should.
I was personally always happier with less money and materials. No stress of thieves. Had everything necessary that the Lord provided. Most of all I had the time to be still, look, listen, and see God in everything and everyone that he made. This made the creations of mans materialistic items more undesirable to me, than what God provided daily. The quest for God and his love grew exponentially. This is my personal perception and experience. I know that many others share it.
I have always said that if you want to really change your world and your life, change your perception and get the correct perspective. That starts with the wisdom of the Lord alone, and nothing that we possess. If the Lord said it, and the Bible teaches it, as a Christian, we know it is true. Yet rich are poor, for those who believe in and serve the Lord, they desire the things of righteousness and goodness from the change of their heart at salvation and through getting in the word.
Thank you for reading. May God richly bless you in spirit my friend, and give you the words from the Holy Spirit to help your friend. Amen.