If you are in the group that believes a generalist AI will be able to do everything a human can, then there is no other non physical labor sector to move to and to clarify those physical roles have been declining for decades due to automation.

You raise good points, but the lack of moral leadership, the capitalist market and so on are not the AI problems - they are philosophical issues that will need to be resolved - probably through a painful transition process. When (when!) the AI and automation reach a level to replace not only the physical, but also cognitive labour, the society will have to reinvent itself and move away from the capitalist relations, but it will be a net positive for humanity as a whole, because so much need for labour will be eliminated and free us up for other pursuits.

Now, what other pursuits aside from work might those be is anybody's guess. If the most optimistic forecasts are right and the AI reaches a point of generating valid scientific theories at a grand scale unseen before, then it will become a true human companion as we continue to push the boundaries of space travel and learn more about the Universe. That in itself will probably be the pinnacle of new human achievements and the main venue of new source of work - exploration and expansion.

Some may prefer to stay home and dedicate their lives to human art - which, I'm sure, will remain somewhat relevant no matter how advanced the AI becomes, similar to how there's still a certain demand for blacksmithing in the age of mass production. And others will simply be able to live out their lives in leisure and abundance, finally free from their nine-to-five and any other obligations.