Besides, what else are we working with here? A man lives a quiet life for 50-some years and then silently prepares for and executes a plan to kill 59 people and wound 500+ more? More effectively than almost every other terrorist and every mass-shooter in recent history? Despite apparently holding no strong political or ideological views?
Guy snaps for some reason or another and goes on a killing spree, sure? Not like you need strong political or ideological views to pick up how to effectively kill people, or that there was really anything special about his methods other than being stable and sane enough/in the right ways to go through with it and rich enough to fund it, contrary to many people who
are motivated in such ways. Don't need a history of mental illness (or actual long term neurological dysfunction of some sort at all) for something to fuck up hard enough to send you temporarily-ish insane long enough to do it, either.
Also more than one sort of brain
damage that can cause radical behavioral shifts, for that matter, which get all the more common as a person gets older. Till we have an actual explanation all guessing really gets us is guessing. At least at the mo' it looks like it's entirely possible this is really
is "just" a rich guy unfortunately capable in the right ways that snapped in the right ways at the right time, without some kind of background more contributory than providing the physical means to make things happen. Also possible it's who the hell knows what else. Still hasn't been 24 hours, I think. Certainly been less than 36. To dig into the life of a person that, as you note, lived a long and apparently fairly quiet one up 'till the end of it.