Also, it omits other trends that can be shown to contradict it.
If massive unemployment ensues, then consumption collapses, which also drives down the price for all the robot products and labor. Yeah, the robots undercut labor, but then deflation kicks in and the robots end up undercutting each other until the point anyone can scrape together enough to buy their own robot to produce stuff for them. Home hydroponics robot which grows food? Good stuff.
Plus, with 3D printers appearing, they make people much more self-sufficient for consumer goods. So goods will be cheaper than ever, and replicators like reprap, which can in principle used ground up recycled materials mean that it's now possible to turn anything into a powder then combine that with a cheap resin to make 3D stuff, in your own home. This will further drive down the costs of corporate produced goods. They won't be able to charge $25 for a dinky piece of plastic very soon. They'll see their margins drop, but will they be more profitable in the long run or will the many competing sources of automation drive down profit margins to even lower than now?
We then have software that can make music, art etc, coming down the line. This will potentially make all skilled creative work obselete. But you know, someone still has to make decisions about what the product is going to be. What the doom and gloom viewpoint underestimates by far is the that the demand for content in digital media is bottomless. What's the ideal amount of detail in a game like Skyrim or Fallout 3? Are more streamlined creation tools more likely to put people out of work, or massively expand the possible content, which actually makes the product better and sell more, thus allowing you to hire more people? Procedural Generation hasn't put anyone out of work, it just allows games to have more content. You don't hire 1000 people to hand-craft a continent in a game: you never did.
Ok, lets say it gets to an end-game where even the creative decision makers who control the game creation process are not needed. There's one fatcat company president in a suit who orders a huge rack of computers to produce a game for him. The software designs and builds everything by determining the optimal game that fills his requirements. Well, the problem with this is, this guy isn't a games designer, he's a useless corporate executive running his 1-man company. He's now even shittier than the shittest indie developer, ever, except he's got shinier toys, because they fired everyone with actual talent to save money. I can't honestly believe we will end up in a world where all talent has zero value because computers. Maybe the needed talents will change, but some people will always have more talent at utilizing the modern tech than other people.
Ok, assuming that firing all creatives wasn't a problem because talent is automated: the question would quickly be asked: why do we need this last guy? Why do we even need games companies and capitalism in our games. At this stage of development, capitalism itself will collapse in the games industry and anyone will be able to create the best games ever for themselves or their friends, given enough processor power.