That is the perception, yes, however it's usually not that.
I have background in education, but not in regular schools.
I was the math and critical thinking lead at a supplementary learning center where we adapted to each student as an individual in whatever ways we could find that were effective.
We had many parents bring students to us. A number of them said their kids were suspected of having ADHD by the public school staff.
95% of the time, it was a misdiagnosis.
In most cases, once we established each child's neurological profile and used that profile to work with the child, the child's performance was excellent.