On a 3rd forum I am on - there is a guy who is a bit of a rabble rouser. He is respectful of other's opinions - but his opinions are OUT there. Most firmly disagree with him - and he is passionate and would not back down. People asked for his banning because of it, but the moderators let it go because he was not mean-spirited about it. Come to find out he had "an event" this past weekend and died almost instantaneously. Amazing how people's opinions change quickly, despite never having met him in person.
I am on another forum where we had a "run" last year and lost 3 people. 2 were active posters even up to the week of their passing.
I myself had not met any of them, nor did I really interact with them on the forum. I know it was tough for some who interacted with them frequently. Because they are not just "deleted" it is jarring to see posts from them in old threads that are bumped.
Sidebar, I recently was trying to find a subject matter expert on something. I knew OF him, and some of his online postings in a multitude of forums. I was searching trying to get contact information from him. I decided to search one last thing and was surprised to find his obituary as a link. Without finding that I would have reached out simply because everything else was still up there.