The "golden billion" people almost all live in luxury, by the standards of an early industrial society like the early 19th century Europe which Marx described, and daily use a ton of amenities which even the mightiest king could not afford 1000 years ago. But we take it for granted.
I could have taken my savings and downshifted to a comfortable life in a third-world country. But instead I've put them in my wife's business, and keep working, while living in one of the most expensive cities in the Solar system. This is because I want a better education for my children, and success for the business. (The city is also enjoyable when I have the time.)
Then, some amenities are still expensive. Think about medical care, especially larger-scale like cardiac surgery. Well, think about the cost of a Claude subscription if you live otherwise happily for $25 / day in an inexpensive third-world countryside.
We work so much because there's still utility in it, in many cases. We have plenty, but not plenty enough.