Americans do not work more than the rest of the world
Despite many reports that Americans "work so much" and they do not get enough "vacation", in actuality, they are just chilling at work more than most countries.
Why do US workers prefer to "chill" at work, instead of with family, friends, or alone?
Is this a good thing?
Are you hypothesizing here, or do you have any actual evidence that this extra time is "chilling", and not "being present to keep up the appearance of working", perhaps because not doing so might lead to being fired or left out of promotions? (If so, I don't think the extra level of stress is compatible with the term 'chill'.)
Or, to go old school on you, are you an apologist for the excessive demands of the capital owners and their managerial puppets?