I don't think they are mutually exclusive but from my personal anecdote (I have ADHD and my S/O has a stutter)...he is the opposite, has everything together, very meticulous, manages time well, no prioritizing problems etc. Now I have met some ADHD people who stuttered, so maybe it's the other way around...maybe some people with ADHD are more likely to stutter. And I can see that bc we are in such a rush to get our thoughts out sometimes that we mess up our speech idk...