I really think some auties need those around them to switch from a "no meltdowns allowed" attitude to a "figuring out the best way to live with an occasional meltdown" mindset. Some of us can learn to avoid meltdowns. Some of us do not have enough control over enough of our worlds to reach that goal. So for those people, the goal should be to make it possible for everyone (very much including the person melting down) to live through the occasional meltdown with as little damage and added stress as possible.
After it's all over and everyone is calm again, those who have ongoing
contact with the melter should try to understand what caused each
particular meltdown, so that more and more causes of meltdowns are
removed as time goes on. But the expectation, rather than being
"meltdown extinction," always should be: less painful meltdowns for all.