Hindsight is 20/20 and the eventual reason for his ban is indeed how disruptive he became to the community, but the focus of staff efforts initially was to reach out and try to help him (and just so everyone doesn't think I'm painting myself as an angel here, I'm going to thank Crash and Tres for that, because I was definitely one of the first staff members to put my hand up in favour of a ban).
This is one of these situations where you can look at it and say this is why we deal with things on a case-by-case basis. Someone who isn't this person, who did actually connect with people on the board, would not have been given so much leeway. It's easy to say now that he should have been banned sooner, but I think it's a positive thing that members of the staff and community wanted to put in the effort to help the guy - as far as I know, the staff didn't even know his personal history.
I had one back and forth with him months ago (where I too attempted to convince him to get help and recognise his unhealthy behaviour) and made it a point to stay away after that because I had made up my mind at the time it would end with a ban at some point. But that's not to belittle the efforts of staff who actually continued to reach out, because everyone was holding out hope he could be helped in some way. The other aspect is that if we'd banned him sooner it could easily have been looked on as tyranny or being unfair to some, but now we can at least say we gave it our best shot (and people really, really did). His story is a sad one to be sure, and as someone who has lost a partner in the past I can empathise with the situation. No matter your condition though, one of the first things any psychologist will tell you is that just because you understand the source of your behaviour, you are still responsible for the impact it has on other people.
This is the difference between us and some other communities. As long as the discourse stays (for the most part) mature and respectful, we're not going to boot people unless there's a good reason to do so and it's well justified. Where places like ResetEra are cities, we are a small town. Everyone kind of knows everyone, and maybe there's a small village pub with an old drunk guy that's a bit of a pain sometimes but you put up with them to a point. On another (larger) board the old drunk guy gets booted the first time he's a pain and never gets another chance.