I think being realistic is important. I taught a child last year with PDA who was working at 8-20 or 16-26 months across the board in year 2, who had no interest in engaging with any learning not of their immediate choice, and mum was talking about GCSEs and Gap years before university. Her expectations needed managing!
I have one autistic child and one with adhd myself and am very realistic about the difficulties they face and the effect on their futures!