Ehh, all very sad and everything, but it's entirely his own fault really.
I've been in the same shoes (suicidal depression, albeit not for the same reasons, but that opace a darkness doesn't have too many hues. Presuming it was related to his increasing irrellivence in the modern world) and he forgot the biggest points, there's always help (& being a multi millionaire I imagine the quality of help available to him would have been noticeably greater than that open to someone such as myself) out there, and that your own opinion of your self worth is only half the story.
I'm pretty sure the cokey yay a head could have made penguin movies for the rest of his natural and still would have been reveered.
Now as I said it is indeed sad and a loss (I never found too great a comic appeal in him, but his work in Poe faced science fiction was more to my tastes), but the greater tragedy is that we still live in an age where a man can trap himself in private agony and not have the depth of their pathos recognised until it's too late and they have commuted that most selfish of acts.