Yeah, right. Back in the days when we were all on forums I got to know a bunch of regulars who contributed on a local site. Eventually we started meeting up and I had a similar experience to what you're describing. I even slept with one of them that first time we all met, we'd been chatting on the forum for over a year and felt like we knew each other well enough for that to be a possibility. Now that I think about it, this is pretty much the principle behind internet dating and that seems to work well enough to have become an industry. I've done that in the past too - you can absolutely build a relationship online and people do it all the time.

my experience with online friendships is that it's much easier to self-select. you absolutely can get to know people really well over the internet, but it's also much easier to completely ignore who seems a bit annoying. at least for me, gathering people in the same room and forcing some physical interaction is more likely to make me get to know the people i probably wouldn't otherwise.

that being said, i think the whole productivity aspect is bunk and bosses want you in the office so they can say the things to you that they're afraid to put into writing. "in person collaboration" isn't code for you talking to your colleague, it's code for bosses want to be able to catch employees in the hallways and ask them to work on pet projects that are outside the employees designated duties or priorities, without a meeting record.