By default doesn't that signal change as soon as you are aware of it?I hope so, and I think it will happen, but probably only when all the people obsessed with books in particular are dead.
People use books as a signal for how smart they are. A smart person without bias uses an ebook because it is more efficient. The signal of people with lots of books then becomes one of someone who likes signals but not reading?
But even if we agree on this I'm skeptical about books losing their signaling power any time soon.
Knowing that we signal for status doesn't prevent us from doing it. People still try to signal fertility by looking good. It still works even though we know people get plastic surgery and have clever ways to hide flaws. Doctors are still high status even though there's little evidence that they do much to help and plenty of evidence that they don't much care that they don't.
It matters more that the signal be hard to fake. It's easy to buy pretentious books, but harder to talk knowingly about them. So the signal is for people who either know about, or care in some way about similar books. We need ways to hang out with people like us without seeming too much like assholes about it.
Often the only thing that counts is that people know what we're reading. We read Harry Potter in public because other people know about it and are likely to be able to chat about it. Road to Serfdom is better on a learned bookshelf.
It's like Trevor's university filter. If we know that people mostly go to Harvard for the signal and to be with the right kinda people, won't people just learn online? It's so much cheaper and more efficient!
The point is not that unbiased smart people will not use e-book's, just that they don't perform some social functions that we to perform sometime anyway.
I'd also predict that people with secure reputations for deepness and learning will be quicker to adopt. Tyler Cowens rather than academic careerists.
Personally I'm fine with telling people that I like having books for signalling. Just so long as people appreciate how profound and self effacing I'm being when I do it.