The fundamental issue to be faced is that there are or will be too many people for the available work.
Depends on your definition of 'work', I guess.
I recall that some years ago, the number of 'information workers' exceeded the number of 'industrial' workers (in the same way that in the Industrial Revolution the number of 'industrial' workers exceeded the number of 'agricultural' workers). So now most people's work does not directly produce any physical product. Instead, they work with information, essentially managing and optimising those that do produce stuff. I see no reason why that kind of work wouldn't continue to be useful.
I'm sure it will be valuable for some time yet. It just wont be done by PEOPLE. It'll be done by machines, far more quickly and accurately and tirelessly than any group of humans could. And it'll be CHEAP.
It's not about too many people for too few jobs. Well, it is, but that is ignoring the real question: HOW do you distribute the wealth of our civilization in a fair way that achieves maximum benefit for maximum people?
It's quite the optimisation problem...
What I can tell you is that what we are doing NOW is not it. It is not even a part of it. It bears no likeness to a working system.
Indeed, I think you could argue that our current world economy more closely approximates a complex MULTI NODE FAILURE MODE rather than a working economic system. It is fault intolerant, buggy and prone to hacking. If it was an OS, we'd call it Windows.
Why do you need to distribute it fairly? I don't understand this need for fairness at all. Some people do better than other people. That's called life. Roman Abramovich has more money than a small country. Bill Gates has twice the entire annual tax take of NZ. I don't regard that as 'unfair' - it merely 'is'.
They are very lucky but I feel no need nor see any particular reason to force them to give their money to other people. Making everyone equally poor strikes me as a bad idea. Yes, some are more equal than others and personally I am fine with that. It's been that way since time immemorial. It will always be that way I suspect, in some form or another.
The wealthy are in a position to influence society to their sole benefit. This is why we see on 68 people having as much wealth as the lower 50% (over 3.5 Billion people).
The wealthy get special treatment from the law, drug convictions get dismissed for the rich and the poor get excessively punished.
The wealthy can leverage tax laws to pay much lower effective taxes that the rest of us can't, because they have been able to influence tax laws.
The wealthy benefit from educated, stable, healthy workforce, that costs money, tax money.