I don’t think it’s fair to say overall reaction has been positive. It’s created a lot of controversy here in Toronto. Here’s one summary of why many parents are upset: http://bloom-parentingkidswithdisabilities.blogspot.ca/2016/10/why-i-cant-be-for-sickkids-vs.html
And here’s some MSM coverage of the controversy: http://www.cbc.ca/news/canada/ottawa/michael-orsini-sick-kids-fundraising-ad-1.3816445
A generation ago people were talking about “curing” being gay. To many of those with autism, talk of a cure is equally offensive.