Yet it happens all the time. They just find other ways of justifying it. Persuading the child to ask to do classes they don't want to because 'that will be easier for you'. Putting kids in lower capability classes and making statements that they can't focus on harder stuff. The system likes out its rear to attack disabled people. And sometimes if they diagnose you early enough then the system is rigged. You are never given a chance to prove you can do better so you slide down until by time high school hits you really are too far behind to break through without massive stress....and if we try that is turned around as proof we couldn't do it in the first place. The whole thing is toxic and it happens worldwide.