Every generation has had to make peace with their existence. For anyone not on eternal morphine drip, lobotomized, or otherwise artificially altered brain, the answer to this is a mental evolution, not solvable just with material possessions or environment.

Social validation will likely still exist, and hobbies. People will continue to derive meaning from these. There will be sufferings over problems and scenarios we consider petty or alien today, and the people then will have to overcome those sufferings somehow if they want to be happy.

And then you'll have the other people/entities: constantly high or who have changed their brain to always be satisfied. They won't worry about these things.