In my opinion: In a couple of years we will not use Emacs or Visual Studio or anything like that: Most of programming will be done socially in Github via small changes directly from the website, from hundreds of people... it'd simplify the process of collaborative programming a lot.
As someone who's been on emacs the better part of a decade now, I find your opinion adorable and invite you to wrestle my editor/ide/im client/mail client/friend/lover from my cold, dead, RSI'd fingers.
As someone who's always worked alone, I also find your opinion adorable, and will code socially when someone manages to hack their way into my ultra secure coding vault. Which I admittedly let people into for pairing. Sometimes.
Collaborative doesn't necessarily mean synchronous. We learned this building the real time building system in second life. Sometimes you just want to sit in your corner and know no one else is gonna come in, and not having that ability cuts off a huge portion of people who just don't work well in that circumstance. It's awesome to work offline, alone.
I'd think that the total SLOC in side/single-developer projects is miniscule compared to the total SLOC in social projects (e.g. Linux, GCC, Emacs, etc.), and even smaller compared to the SLOC in private/corporate code-bases.