This isn't specifically with/without ADHD specifically, but here's what I think:
No comorbidity of any kind is like... A plus and/or minus zero of whatever you're born with, whatever you also grew up with, and how *you* are with.
As an autistic and about autism without any comorbids to speak of:
No ADHD to me means hyperactivity, impulsivity and inattention, or just the lack of means of intentionality 'can happen'.
No anxiety to me means impending doom, aversions, nervousness, sensory intolerances 'can happen'.
No depression to me means numbness, emptiness, lack of whatever 'can happen'.
No learning disability to me means clumsiness, misreading, mishearing, miscounting, miscommunication, etc... 'Can happen'.
No GDD nor giftedness means both or either being delayed and being advanced 'can happen'.
No sensory and emotional sensitivity/insensitivity/aversion/seeking, to have or have not the means to distinguish in-between, to be responsive or irresponsive... Yet, 'can happen'.
Not being nonverbal or verbal 'can happen'.
Not having a burnout, yet means burnout 'can happen'.
Not having trouble passing, and yet not able to pass, 'can happen'.
PIQ/VIQ just determines the best work around to access, neither are really better nor worse than another.
Innately, I'm PIQ>VIQ/abstract/lateral/emotionally nitpicking, but VIQ>PIQ/concrete/literal/alexithymic 'can happen' too.
Just so happened that I know how to escape cycles or being stuck/fixed on certain points... Yet being trapped in cycles and being stuck, 'can happen'.
That's the best way I could describe it for now.