Let me put it this way: Too many people have used phrases like that for me to NOT challenge it. Hitler's Final Solution for the Jewish Problem started with a test run on Germany's disabled population. My point, however, is that kids who have disabilities need to learn how to act from kids who don't.
Put a dozen kids with Asperger’s and Autism in the same room, and let them learn each other's bad behaviors? I've seen it. It AIN'T pretty. My son was there. He wasn't particularly verbal, but he was no head-banger. However, some of his gen-ed teachers thought he was horrifying, because he didn't answer them when they talked to him, or if he did, it wasn't a direct answer. He used, at the time, verbalizations from his videos and movies. Getting an immunization, he chattered about a little girl going to the doctor, for example. He couldn't express his concerns any other way. This was at 2 years and older, until he was about seven or eight, and after using five-word original sentences at 18 months. Now, most people who talked to him wouldn't recognize that he had a disability until they noticed that he was seriously into things most people don't care about. His thing is Animation. It's sort of like talking to my brother, the gun nut. For years, all he talked about was handloading with his Dillon progressive reloading press. Bullet shapes, and diameters, and weights, and powders, etc. I like guns, and I've reloaded on and off for over 40 years, but...
Anyway, my major point is that segregating them has been tried. It did not work then, and I doubt it will work now. Learning how to deal with their issues the most effective and economical way is what we need to do. And, unfortunately, one-size-does-not-fit-all with disabled kids. Heck, it really doesn't fit all with non-disabled kids, for that matter. My son never hurt anyone intentionally in his life. His kindergarten teacher was initially terrified of him, because she had a nephew with Autism who was violent and unpredictable. (To people who didn't know him, anyway.)
No offense, but that sounds very similar to the liberals' conclusion that black kids need to sit next to white kids in order to learn.
I think I understand where you are coming from, though, and where you are coming from is based on your personal experience. I respect that, I truly do. Your opinion, however, does provide a clue about why so many caring parents have abandoned the government schools. It is because they want their kids to soar to the highest level possible rather than merely acclimate to the lowest common denominator. That is, they don't want to sacrifice their children's education just so their children may be used to serve as examples, or models, for other kids.