Working isn't the only way we humans can enjoy a worthwhile, meaningful life though their activity might not be productive nor counterproductive for a society. So NO, a human world where everyone is expected to or gets to work, need not be as long as a basic income or credit source is provided. With far less humans and changes to our many negatives existing with long term, harmonious, balanced, environmental sustainability, AI increases in medical science providing much longer lives, freedom from fossil fuel source energy, this amazing planet in a future technology age could be an absolute paradise.
That noted, one can also predict that there are many people today with weak self control that if they did not work and were just paid a basic income, would descend into some psychologically addictive feel good or numbing drug, excessive food obese, fitness poor, unnatural sex oriented, gambling for $$$, foul existence. So in that regard given our current human world, regular 8-5 m-f work keeps many people on a reasonably even keel.
Many other people for entertainment depend on watching movies, tv, especially watching tv pro sports, watching others do things instead of participating themselves. If those folks were suddenly cast out of a working world, many would not find their way into an alternate healthy lifestyle. And yes there will always be plenty of productive jobs like in the sciences and technology for some to immerse their lives in. But realistically in the near century future, probably not enough, soon enough, to successfully spread across the way over-populated human world we now live in.
It is those with hobbies and active physical pursuits, especially outdoor activities that won't have trouble in a workless world with a guaranteed income. Only about 50% of people have hobbies today while what qualifies as a hobby is a vague term. Hobby goes beyond creative activities if one includes having fun, playing. Does playing video games qualify as a hobby? Maybe, but ought be put in its own category as it may become psychologically addicting in negative ways. Generally the more technologically capable and educated one is, the more interesting life can potentially be. And that is especially true for those knowledgeable about natural sciences like this person. I could easily spend an eternity here on planet Earth enjoying, studying, experiencing its myriad environments.
And besides hobbies, many people will always be able to enjoy learning, educating, enhancing their minds in myriad ways that are not necessarily to make $$$. The more one educates one's mind, the more potentially interesting a life can become. Heck, just studying history can immerse one into an immense journey of knowledge.
And for the physically fit, especially those young and fit, there is a vast world of active physical possibilities the majority of working urban people never develop interests in. Many never had the time as they spent their lifetime pursuing, struggling for money, allowing their bodies to degenerate from what they were at 20. Like playing all manner of sport games from golf to team basketball to team softball to table tennis to surfing to snow skiing to fishing, to climbing, to sailing, on and on with possibilities.
And what will future amusement parks be like? Yeah lots of thrill rides but how about underwater ocean tunnels with viewing portals where people get to watch all manner of ocean life in natural ways. Or free to visit parks on idyllic tropical corral reef surrounded islands or high alpine mountains, or some fantastic temperate redwood forest.