Can you imagine sitting in a school assembly where the speaker is telling everyone how awful autism is, and we should raise money for the poor autistics-- and you have it?)
Yes, I can imagine that - but I don't really want to.
I'm sorry that that happened to your son, and I'm glad that he is able to challenge such things now.
Actually, it turned into a very funny situation; the speaker had no clue what DS was talking about for a bit (he raised his hand and was called on...), and DS was quite clear about what autism isn't.
One of our school allies emailed me afterward-- she was so proud of DS for speaking up in a calm and humorous way, and so am I. :-)
If you've got to be different, might as well be different with style.