Children with severe cerebral palsy have better emotional well-being, a better self-concept, a happier attitude, less bullying, and more acceptance than children with mild cerebral palsy. In fact, if you didn't count physical well-being and independence as measures of quality of life, the quality of life by the measure they used (which was designed for typical kids) was pretty even across the board for the severely and mildly affected kids; in the subfacets above, it was higher... The only things that reliably made quality of life worse were chronic pain and parental stress.
I am really pretty sick of people assuming that quality of life gets worse if you are disabled, and gets even worse if you're more disabled. You can't make that assumption. Life is just life, and I am really tired of people saying either "But your life would be better if you weren't disabled", or "You can't imagine what it's like to be more disabled."
It's like being stuck in the middle--I'm not disabled enough to really know "what it's like"; but if I were more severely affected I wouldn't be able to talk to tell you I was just fine the way I am.
Duh: I don't know what it's like to be another autistic person. But that's true whether or not we're functioning at the same level. Nobody ever knows what it's like to be anybody else; we can only imagine. Problem is, some people assume they know.
So basically, using that reasoning they can just proclaim that if you can speak, then what you say doesn't matter; if you can't speak, then they'll just assume you're not happy and try to mess around with your brain. Never mind that 'speak' doesn't mean 'communicate'... but no, they don't listen to that either half the time. People ought to learn Autism As a Second Language in high school, really.