The worst of it has almost certainly been deleted / cleaned off.
I agree that he was valuable when he was contributing knowledge. I also agree with @SuperTachyon about the “authoritative” thing.
Here’s a random example from another post:
The background is that I’d shared something that I rather vividly recall happening a few times, although I couldn’t cite an example. He demanded hard proof. I obviously didn’t have any, so he insisted I was misremembering, and that the thing I remembered never happened.
And ended by utilizing the rather offensive phrasing below.
Linked so you can feel free to go read the whole thread if you like.