With a good investment stratagy you can live off of ~4% of your capital per year and keep up with inflation. 4% of 5M is 200k/year. But if your retiring early you should aim for a 50% cushion which works out to 133k/year which far from amazing when you need to pay for your own heathcare etc.

PS: Rich means "Possessing great material wealth" which I think it stands for more than just the ability to support an upper middle class lifestyle without working.