This is a very interesting topic imo. I wonder if there are statistics somewhere on it.
I know many people who have died close to each other in this way, and I suspect that my in-laws might go like this. But you are right, the internet has changed things in this regard as even if they don't actually connect with people, they can feel more connected as they are more actively consuming, rather than passively - especially for the older group.
It would be a fascinating study.
Before retirement I drove everyday of the week, I would spend 4 or 5 days a week surrounded by co-workers, sometimes a lot sometimes not so many. Just prior to retirement I started to take notice of some of the people that retired a few years ahead of me. Some would sit at the coffee shop sipping coffee all day and just passing the time away, others would hit the bar, a few would re-turn to work to hang out.
When i retired, I was done working, and meaningless conversations...well had no meaning anymore. It took several years for the driving habit to stop, I still have an itch between 1 and 2 pm to go somewhere to do something, because I was a shift worker for so long and that was the most frequent time I went to work.
I think there are a few things a study would show, those that retired and did nothing, (me). Those that retired and died of boredom, and those that retired in name only still working and doing things with people only not getting paid. Retired life is strange, and I think different for just about every individual.