I have an adult stepson from my previous marriage who is very low functioning. He has autistic behaviors, though his several other diagnosis preclude him from ever being classified officially as autistic.
He has lived in a home since he was five and I used to be a part of his team that would help to decide his care as well as around his home and the people who lived there.
When he was younger, I didn't appreciate all that his home did for him - really what was the point, he was so low functioning? It wasn't until he was in his teens and some new kids appeared in his classes and his home that had never been in a school environment that I started to understand how valuable the care he had gotten had been. I met, for example, a teenage girl, blind and nonverbal, whose parents had cuddled her a great deal, never thinking that having a teenage girl who hopped on people's laps might not be the situation they wanted to groom her for. I saw another girl, confined to a wheelchair, coming to school for the first time with no idea how to behave in a classroom and no ability to receive instruction. Whereas, with my stepson, he grew from a loveable young man into a manageable and pleasant adult whose care team made sure he was not overfed, that he would no longer have to be physically manipulated to get dressed but could do it himself by the time he was too big to be dressed by someone else. And so on.
Every year they'd close the home down at Christmas time to give the staff a break and he'd come to our home. It was tremendously isolating (no one would visit us or help us) and tremendously stressful to have him just for those few days, even after he was potty trained (at age 10 - but still needed a diaper at night).
A lot of people with special needs kids get so caught up in the day to day that they forget about what kind of adult they need their child to be. People really need help - these people obviously mistreated their children and don't get a pass for not finding the help they needed, but I agree that getting more help for this family is the way to go unless it really is determined that the parents were totally heartless in their care.