I initially thought the same thingabout happiness, but the problem isn't in their 20s while they're relatively healthy and have their whole lives ahead of them.
Will they still be happy and fulfilled bagging groceries for half a day and going home to play GTA12 on their MagicLeap...rather than going to the doctor for that weird shooting pain or the cough they couldn't shake after being sick half the summer?
Will they simply opt not to get married? What about having kids? Both would be hard to reconcile with such a life -not saying anyone must or should do those things, but some might feel differently at 35 or 40 and find it hard to switch gears.