We stopped with agreement from her, taking Ritalin. That is such a terrible drug

It's terrible for some people; others tolerate it well enough for a long time that they don't need any other treatment; for others it's a not-too-bad temporary measure to calm the whole situation down when starting some longer-term strategy. You're suggesting it should be banned, based on a sample of one? A parent of an ADHD kid is likely to end up messianically for or against it, depending on what happened with theirs; someone who sees how hundreds of kids react to it will be less likely to go to extremes.

I suppose you are going to tell me that Autistic children can be cured now?

Only very rarely (taking "cured" to mean "nobody could tell they were any different unless they asked"). But a great many can be helped by appropriate intervention, and the earlier it's done the more likely it is to be successful. (GF/CF diet in particular; waste of time trying years after onset). Getting from total muteness and faecal incontinence to complete sentences and normal toilet use is not cure, but it makes a big difference.