Earlier quoted context omitted.
That's a vacuous argument. It's true for literally anything. an excessive consumption of water is bad, drinking the right amount of clean water is solely beneficial an excessive consumption of eggs is bad, eating the right amount of eggs is solely beneficial an excessive consumption of toxic sludge is bad, eating the right amount (0) of sludge is solely beneficial The question, of course, is what is the right amount…
This is such a disingenuous reply. We are not talking about cyanide here or some strange nutrient that you can overdose if you're not careful. A serving of whole grains every day (just read the back of the box if you're unsure what the quantities are) is solely beneficial for you and unless you have a medical condition you simply can't go wrong.
I agree there is a non-zero amount of grains that is healthy to consume, but your answer doesn't say anything about what that amount should be, and as such just states something that is pretty obvious. It would improve your answer a lot if you stated which quantities you are thinking of, and even more if you include sources.
From your original comment I honestly was not able to tell that your recommendation was to eat cereal daily in the amounts recommended by the back of the box.