That was true in the 50s/60s, but times change. Poverty today is triggered by a great many things. Today, a health crisis can destroy anyone's savings. A decent living wage means nothing should you or a member of your family get cancer. Either your have to sink all your savings into treatment and associated support or you have to stop work to take care of them yourself, mooting the wage issue. Retirement is also different today. With interest rates essentially zero, a decent wage during working years cannot provide sufficient savings for a multi-decade retirement. So people need either good pensions or ample investment opportunities. Today that is being funded by real estate but that cannot last forever.

Looking at someone's entire life and the likelihood that they will suffer poverty, their working wage is only one of many factors.