I agree that it's ridiculous.
I'm not sure how to get from there to "screw copyright." Yes, it's weird that the law requires (at least under normal circumstances, and if the Internet Archive is wrong, also today) physical copies of books as essentially "reserves" for scanned versions of books. I don't think that it follows that it's weird that the law requires that you have to pay per copy.
In the pre-digital world, if a library wanted to lend out ten copies of a book, they'd have to pay for ten copies, and that wasn't weird. And this isn't an argument about zero-marginal-cost products, because a good chunk of the money the library spent would not go to the physical cost of book printing. (In fact most people's intuitions would say it's fairer that there's a profit beyond the marginal cost, because that way the author and editor get compensated more for more successful books.)
Yes, it'd be significantly better if the Internet Archive needed to have one physical copy (or even zero). I don't think it's weird that if they or any other library wants to lend out ten copies, they have to buy ten copies.
(I'm sympathetic to arguments of the form "information wants to be free," but, well, people want to eat, too. If injustice A is mitigated by injustice B, snapping your fingers and getting rid of B without having a plan to deal for A isn't a just action. Whether or not authors should depend on copyright for their livelihood, many of them do. And yes, several don't - so in particular, I'm much more sympathetic to the Internet Archive's action when it comes to textbooks, journals, etc. written by people who have a primary livelihood other than book-writing, such as college faculty, and much less sympathetic when it comes to books written by people who's job title is "author.")