I'll agree with Nornagest on the insult to injury part, but there's also a second part:
If you talk about someone's failings after they die, but not before, then you seem to have been waiting until they were no longer available to defend themselves.
IOW: it seems cowardly, and dishonest. Because if they were still around, they might be able to dismiss your allegations.
Can I mitigate people's negative feelings by mostly offering cites of old criticisms?
First, Darwin describes Jobs's (far mode) stance towards death:
But these are Jobs's actual (near mode) actions regarding his own death:
The conclusion: