He is just saying that it would have probably been far more useful to do it while he was still alive, which is sadly true.
Being said, I agree that's it's a nice move.
Edit : I should add that I believe there would have been a meaningful backlash had he for some reason lost his criminal case and been sentenced to (n > 3) years in federal prison.
In hindsight, there was a great deal of empathy to be shown to an individual who was being financially and emotionally drained by the legal system. However, that's the sort of stuff that doesn't readily occur to most people (myself included).
A Redditor started the campaign to raise $700K for the bullied bus driver. How easily that could've been raised for Aaron