jgbrowning said:
Yes, it would seem that this criticism about Eberron does punch your mom on the head at least.
Perhaps it's not criticism about Eberron per se, but rather the tone of (some of) the statements of said criticism. That said, as others have said, I wouldn't dismiss the criticism itself. It does seem fairly easy to solve, and many have mentioned it.
That said, D&D, given its rules & peculiarities, always struck me as a horrible system for a simulationist (barring some very odd simulations). Any simulation that has to take into account a few fully-equipped 16th+ level fighters (who could probably demolish an entire army, if you assume the standard "most people are 1st level") will tend to fall apart, get really contrived (e.g., "they all cancel each other out!"), or become rapidly alien to most gamers' tastes. Then try to deal with 16th-20th level spellcasters (let's not even worry about epic level spellcasters, interventionist balors & solars, active great wyrm dragons, or the like). We also won't mention the default economy.
I'd think population density would be a trivial problem, in comparison.
(Besides, it's like old-school World of Greyhawk! Remember the original population figures of that setting?)
(My own simulationist D&D bugaboo is the insistence that most people are first level; that they never become more competent than they are at the beginning of adulthood. And that they are forever to be in danger of fatal injury should a small housecat become angry with them.

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