Your link does not support your claim or in fact mention living standards at all. The fact, widely evident to every American not in the upper 20%, is that your paycheck is bigger, your house is worse, your food is worse, your healthcare is worse, your life expectancy is worse, your children’s education is worse, you have less free time, you can take fewer vacations, and you can buy less of what you want.

The US was #1 on the Human Development Index in 1995, and is now #20, sandwiched between Slovenia and the UAE.

What your link does show is widening income inequality.