Is Academia.edu decreasing scholarly communication?

I love Academia.edu - I think it's a fantastic way for papers to reach the broadest possible audience, and it's made me aware of many studies I wouldn't have otherwise heard of. While I'm not necessarily the best Academia citizen myself (I really should start following some people), it's really been a tremendous help in tracking down some papers published in obscure sources that might have otherwise taken me an eternity - well, a few days/weeks, which might as well be an eternity in this internet era - to get my little paws on otherwise.

That said, the other day, I was reorganizing one of my filing cabinets and came to my offprint section. It was great to look at these things again, and seeing some of the personal notes written to me by the authors reminded me of how I first got in touch with some of them, in some cases even before pdfs had become the de facto offprint. What I thought was cool about it was that getting these documents required some kind of direct interaction with the author(s), which helped broaden the range of scholars who would have at least a faint idea of who I was. In some cases, these first contacts laid the groundwork for lasting friendships and even eventual collaborations. The personal nature of these contacts also was part of e-mailing folks for pdfs, once these had become well-established enough, in that you'd start a conversation.

But now, with Academia.edu, sometimes I wonder if the opportunity of these contacts has been lost (or at least decreased). If so, it would mean that something that was instrumental for my personal development as a scholar would be lost to people starting out now. I mean, sure, you can see who accesses certain papers, but that hardly counts as a meaningful interaction, no? Even if you do look at who downloaded a file, it's not like most people will remember this for very long, so that even if you do run into the downloader at some point down the line, the relationship will have to begin from scratch. Unless of course, the content of your paper has pleased or irked them enough to e-mail you as a result...