To my knowledge, it's part of the broad criticism that Yudkowsky doesn't seem to have any concept of avoiding overpopulation or general overconsumption of resources. It's like when people go around saying God gave us the Earth to exploit, except with an entire 14-billion light-year-wide Hubble Volume.
Given his focus on transhumanism related issues, it's likely that he has spent more time thinking about overpopulation than all but an insignificantly tiny proportion of the population.
"To your knowledge?" What, do you not know what point you're actually making?
More seriously, I don't think that's an accurate comparison. What fundamentally is the problem with the people saying "God gave us the Earth to exploit"? Well, it's what you said, overconsumption. But what is actually wrong with "overconsumption"? (That is to say, at what point does consumption become overconsumption?) Is there something inherently wrong with pumping lots of oil out of the earth? No, of course not. What's wrong with consuming too much now is that it leaves less for us later. Or that it has other ill effects, such as polluting the atmosphere and making our environment unlivable. There's nothing wrong with unbounded amount of consumption per se if we can find a way to deal with the ill effects (and make sure to leave enough for future people). The value against overconsumption is instrumental, not terminal. If you are in a situation where such consumption would cause a problem, well, don't do that then; but if you're not, go ahead.
Similarly with overpopulation -- there's nothing inherently wrong with a universe full of people; the worry rather is that you'll have so many people with so little space and resources for each that they'd have a terrible quality of life. Once again: Well, don't do that, then! Anticipate problems and avert them (or fail to anticipate them and then solve them, possibly by reducing population or consumption). Eliezer Yudkowsky is not suggesting anything close to the idea that we should make as many people as possible even if all of them would be miserable, or that we consume every resource as fast as possible even if we render the world uninhabitable for our descendants.
In short, the problem is not a large population, nor lots of consumption, but the side-effects of these things, and the shortsightedness that leads people to disregard them. Gotta maintain the distinction between terminal values and instrumental ones.
...OK, there is one obvious thing I'm glossing over. Namely, the idea that it's good to leave some space for the non-humans, as well; their disregard for other forms of life is I think something else we would agree is wrong with the "God gave us the earth to exploit" people, and there the comparison with Yudkowsky is perhaps a little more accurate. But, regarding animals, I don't think Yudkowsky's position is really different from that of most people. Yes, we'd like to have a world with, say, polar bears in it, and not just ones in zoos, or ones who are miserable all the time; but we probably wouldn't want to have a world that was partly ordered according to polar bear values. (Whatever that means.)
Now, other intelligent forms of life is a another can of worms, but I don't think the "God gave us the Earth to exploit" people worry much about those, so I'm going to stop here because I don't really know how to compare there.
(Also I'm not really sure that your earlier "tiling" post is really an accurate representation of Yudkowsky's ideas, but I didn't really want to argue about it, partly because I'm not prepared to right now and partly because it seemed essentially irrelevant.)
You know, as opposed to not tiling the universe in anything.