Coming from a kid who had these same issues…as i have gotten older I have realized at how I can be a slow learner, and maybe didn’t develop as fast as my peers- therefor I really struggled in school. For the sake of trying to keep this short, lets basically say a lot of the time I will look back and wonder if things would have been different had I been held back a year. I truly with all my heart think it would have helped tremendously.
I understand it may not be well looked upon to some degree for being held back, but in all actuality those factors ( plus or minus other ones) won’t matter. There is no harm in holding one back, especially when having ADD. I wish my parents had done it with me. Though is seems like such a small change, I believe it can truly make a significant impact on the kid ( for the better) by holding them back- especially after explaining what you just said.
It is hard for me to admit this myself, but if I can help a kidd, who struggled like me ( though you never would have known from just being around me in a non academic setting) then it is worth it.
I think people with ADD and learning dissabilities can be very smart, and actually interest and wanting to be able to be good in school, but sometimes our brains just develop at a slower rate.
I hope you get what I mean on from this long rant, but I am in my early 20’s and somehow that is one thing I see being a core issue that could have made a world of different, which has this big regret feeling in my mind- though I never thought about it as an option at the time.
At the end of the day, only you truly know what is best.I hope I kind of helped. Best of luck!