I don't think the author is claiming that more expressive or rewarding friendships form as much as he's claiming that remote really makes you focus on the meat and the content of the colleague's output. That's actually something I LOVE about working remotely. There are far fewer politics because instead of saying "Oh man, Jimmy looked at me cross-eyed last week, I don't want to do anything with him anymore", you just say "Oh, Jimmy needs help on this issue. I'll send him a reply in a minute."
I have literally had colleagues complain that they were offended by the way I sat in my chair (and, I've since learned that at least one of my friends has been subjected to this same criticism at a separate workplace). Remote work strips away all of that inconsequential crap and leaves you to focus on the data.
This is one of the major unsung benefits of remote work: it removes a huge amount of office politics and allows employees to concentrate on working and think less about campaigning.
I've had colleagues resent me for not bringing enough free snacks into the office when I was in a supervisory role. Yes, really. Anything that can help mitigate that kind of thing is great.