RC, I don't think there's any legitimacy in Hatchette saying they can't grow their business because of indie authors, any more than if they said they can't grow their business because HarperCollins sells books too, or any other competitor for that matter. Yes, indie authors are competing and taking market share, but a company can't point at a competitor's success and claim that's the reason they themselves are not succeeding. Not if that company expects to turn things around.
Indie authors have more flexibility when it comes to pricing, but only compared to big publishers' refusal and/or inability to be flexible. While the flood of super cheap or free indie books is considered a problem by many (I'm not sure on that one), there's no clear data that suggests readers will eventually refuse on the whole to pay a reasonable price for an ebook. The people who refuse now are the ones who previously shopped at second-hand stores; they are bargain hunters whether cheap ebooks exist or not.
The money publishers make off ebooks is almost entirely profit (HC leaked some data on that awhile back), so there is no reason they can't lower their ebook prices from $13.99 to $6.99 or $5.99 to sell more units; they have no production costs as with hardcopies. In fact, some publishers have already begun to experiment with lower ebook prices. Some have been trying BookBub ads. Some have been trying digital-only imprints releasing several books a month to keep up with the fast-producing indies.
I have no idea if Hatchette is trying any of these. But if they are failing to keep up with the market, it's not the market's fault. If they are failing to keep up with their competitors, it's not their competitors' faults. While there may be a certain amount of cause and effect in play, when it comes to blame, that lies solely with Hatchette. Even if Hatchette's comment wasn't meant to be blame, as you suggest, the attitude behind the comment is the same: "It's not our fault."
As for the pool of authors interested in traditional publishers being detrimentally small, the large majority of self-published authors tried querying before they self-published, they plan to query after self-publishing, or both. Even if the pool is dangerously small, consider why indies are turning away from publishers -- largely due to the standard contract terms. There is nothing stopping publishers from opening up contract negotiations for copyright duration and reversion, non-compete clauses, royalty percentages, guaranteed marketing, author input on editing or covers, and so on. Virtual hordes of indies would come knocking.