Looking at your third link about diagnosis in adults (which I think is most relevant to the discussion here), it provides a good overview of why overdiagnosis w

Looking at your third link about diagnosis in adults (which I think is most relevant to the discussion here), it provides a good overview of why overdiagnosis would be bad and how to potentially avoid it, but it doesn't actually try to answer the question Is Adult Attention-Deficit Hyperactivity Disorder Being Overdiagnosed? I think it's fair to use this paper as evidence that some psychiatrists are concerned that overdiagnosis may be happening, but not as evidence that it actually is happening.