I'm not following your extension of artificial scarcity to Google. Do you mean that because PageRank isn't public, it's artificially scarce? That doesn't seem to hold water....there's no anti-user conspiracy theory required to understand why PageRank is private, but rather the fact that it would rapidly render Google Search pretty useless, due to the strong financial incentive for publishers to "teach to the test". A federated Facebook with public APIs would add to user surplus/utility, while a system based on a public PageRank would rapidly degenerate into a measure of how good a website is at matching PageRank, which would waste a ton of resources _and_ make search quality much worse (again, destroying user utility).
Maybe you've misunderstood what artificial scarcity and rent-seeking mean. She's talking about it in the widely-used economic sense of "scarcity that's imposed solely to extract rents, inferior to an alternative method which would increase net utility". A federated Facebook and open-API Windows both fit this neatly[1], and a public-PageRank Google doesn't even come close.
[1] One could make the argument that Facebook needs to be closed for reasons that benefit the user, but I've never heard any compelling arguments for that.