I think that robots will be able to perform any job in the future, but will people be willing to stop working at those jobs? People need a sense of purpose in life. They may find that in charitable work, religious beliefs, raising children, artistic or scientific endeavors, exploration, or other types of work. There are people who can find joy or meaning even in jobs that may seem to others undesirable. Take the Pike Place Fish Market in Seattle as an example (What is Fish! Philosophy and How It Can Change the Way You See Your Job | Success by LiveChat). Their fishmongers enjoy going into work and tossing fish around. They’re not curing cancer, yet they’re able to find pleasure in a job that perhaps you or I wouldn’t. (You can learn more about Fish! Philosophy here: The FISH! Philosophy Story.)
No, I don’t think that robots will work instead of humans, even if robots are fully capable of doing so. I’m sure humans will continue working, too. Would a musician stop playing music simply because a robot can do it, too? Would a scientist stop probing the secrets of the universe because an AI is also thinking about it? Would an athlete stop playing basketball or an engineer stop designing circuits? No. Most of these people don’t consider what they are doing as “work”. It is pleasure. It’s enjoyable and gives their lives purpose.
I think what will change are the economics of work. Instead of forcing yourself to go into a job that you don’t like just for a paycheck, with the right systems in place, people will be able to do the work they find interesting or important. If we live for a hundred years, we will want to give that time some meaning. Sure, there may be robots also doing that work, but they will be working cooperatively with us simply because we won’t give up those jobs! Robots will take on most, if not all, undesirable jobs, freeing people to “work” at what they enjoy. If everyone is doing what the enjoy, they will naturally get better at it. Ultimately, I think this will improve the quality of the output of human work.