It's internalized ableism related to being told their whole lives they're so smart and talented if only they weren't so lazy. We're extremely capable - sometimes. The rest of the time we struggle at the most basic of everyday tasks that normal people find trivial. Now combine that with late diagnosis. That's a lot of years being told you should be better and wondering why you're not. At the very least, it's an extremely specific kind of low self esteem.

It may not be solely caused by dopamine levels, but the experience is common among many ADHD sufferers and our brain chemistry does predispose us to responding to that in certain ways (which is why we can break out of that pattern more easily when medicated).

While you're right that it's not an explicit ADHD thing, it is very much a symptom of it. How To ADHD made a video about motivation and points out some of the emotional aspects of it here: https://www.youtube.com/watch?v=OM0Xv0eVGtY which can cause the problematic low self-esteem and people-pleasing behaviour. But there has been a lot of connections with ADHD and Rejection Sensitive Dysphoria which can further connect to the behaviours in the OP.

Another good Additude article was written from a question sent in, "How can I stop people-pleasing at work?".

In short: Everyones ADHD affects everyone differently but this definitely has strong connections to ADHD.

Nah, I have that that behavior and crazy high self-esteem. I'm genuinely convinced I can be the most competent person in any situation and I'm usually right.

C-c-c-comorbidities!

Yeah this sounds like it could be CPTSD or part of a personality disorder, which you can often find in people with ADHD (myself an example woo).