I think there are two things to consider-
1- Autism is a very recent thing, although I can see myself clearly in the new understanding of how women and girls can present, no-one knew about it when I was at school in the 80s. Even now, a lot of teacxhers don't have a very good understanding of autism, and don't recognise that there's something else going on until a major problem occurs.
2- It can very much depend upon the teacher. One teacher where I work has identified that a child may be autistic, and is desperately trying to persuade the parents to get him diagnosed, but they are the ones who are refusing. Other teachers, even when I tell them what an SEN child needs, can't be bothered to do the extra work, or they legitimately be too busy and not have the time to do all the extra work.
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Your neurodiverse (Aspie) score: 149 of 200
Your neurotypical (non-autistic) score: 73 of 200
You are very likely neurodiverse (Aspie)