Money is a means to an end, and being happy is a fine end. I only live once and if I can be happy, well then I've pretty much won. Also you're not going to "get rich" by renting, if (and it's a huge if) you can somehow make renting work in your financial favor compared to buying, it's going to be a tiny bit better. You're not going to 10X your income renting.
He also completely discounts the cost of moving constantly (aka "flexibility"), movers, deposits, furnishings... it's not cheap. Yeah you can move yourself (add in the cost of vehicle to make that happen) but it's going to take time, and time is money.
This is not a well thought out article.