I have adhd too, but cannot use stimulant medications (they are too strong). I've had to use non-stim meds.

What if long term caffeine use causes some of the adhd symptoms? It interesting to ponder because if I stop using caffeine for a month, some of my adhd symtoms go away completely. I've done stints of complete caffeine breaks, content consumption breaks (one week or more without screens) and I felt amazing and alive. The first couple of days of using caffeine feels amazing but then I feel dead inside again and live like a robot. So in my mind, caffeine is my main target when I try to adjust my routine/behaviours.

It's not, really. Coffee is an anxiety and insomnia machine for me, while nothing made me as calm as amphetamine (even my heart rate was lower).

I do have a professional diagnosis for ADHD.

Hmm, this is an interesting observation. I do have signs of ADHD.

I really only started drinking coffee at my first real job after grad school. They had free coffee in the kitchen, so I'd occassionally have one. Maybe once or twice a week. I was like that for several years, and would occassionally go weeks without a coffee. During that time, I was very productive and went from being a new grad to leading the entire team of veterans in less than five years.

After leaving that job, I now consume fairly regularly (for the past decade at least). I can still easily skip days without coffee, though I do prefer having it daily. I literally see no difference in my day to day between having coffee and not throughout my two decades of experience with coffee. I can just as easily fall asleep after a coffee and I rarely feel amped up from a coffee (if I do, then I just stop drinking it). I've certainly never felt anhedonia like many others have mentioned in the comments when I've taken breaks from coffee.

I think it's clear that people have different experiences with substances. Whether mine is a common one or not, I cannot say. But I do have a baseline to compare to and I can legitimately say the only thing that has ever caused me anhedonia was burning out from too much work (during burn out I was still consuming coffee and it didn't improve my mental state at all).

My prior would rather be that people have wildly varying sensitivity to caffeine genetically. Some get panic attacks, some don't feel much.

Only true if they drank a cup of coffee since their earliest memories began.