It would be child's play to maintain artificial scarcity. If you're a member of the ruling class who's power, wealth and prestige depends on that scarcity it's in your best interests to maintain it.
That's where the Cyberpunk comes in. Tribes and groups building alternate societies and cultures utilitzing technology salvaged from the mainstream or built as an alternative to established ways of dealing wiht things. This always happens. Only the revolution in tech is rarely violent in a classic class-warfare sense. It's simply people building alternatives to systems that don't work. As technology get's cheaper that becomes easyer for more and more people. One trait of the age of cyberpunk is that cultural and economic spaces aren't spacially divided but stacked on to each other and basically spread out globall - which is a side-effect of current developments. As further advanced technology gets, the easyer it is to actually implement marxism, because it becomes easyer and easyer to take what I need without taking away from others. See FOSS for a prime example.
Likewise, maintaining artificial scarcity is pointless when what I need can be provided faster and easyer by robots than the people I would want to control. There is no incentive anymore to control people beyond a certain point in such a society. It would be more trouble than it is worth and is much better done by netflix and facebook than with all-out opression.
What I'm doing right now I can do in just about any part of the world thjat has an internet connection. A sign of things to come. Yes, sure, Google or some other megacorp will own everthing but it will be so dirt cheap to use it and so costly to deny it to people that we can very well have an Utopia.