As a teacher, I came to the conclusion that these conditions have always existed, but that the milder forms never really became noticable in the days where there were fixed boundaries for what children might do, or certainly where not allowed to do.
Children with the milder forms of these conditions, and in some case also those with more serious forms find life easier, if there are sensible rules which are adhered to.
These must be expressed kindly and politely - no child likes being ordered rudely do do anything, after all.
It is also important that the adults teaching the child, or looking after him or her, or in any way contributing to the child's upbringing, agree on the rules and neither bend them, nor ignore them.
Simple things like ensuring that a school-bag is packed with the right books and colour-coding books, jotters and the written timetable, so for example all books for English had a red label, all maths books a blue, and so on make life far easier for these children.
Modern parenting and teaching tend to think the fewer rules the better - fine if a child is old enough to administer this freedom, but chaos is the result if they are not old enough to remember their gym clothes, lunch money, maths books, or to write down their homework is without being told to do so.