Hi & welcome, blackandwhite34521.

I think ADHD struggles with "executive functions" in the brain could relate to this (at least as far as holding things in one's mind being harder for types of thinking that aren't "rewarding" enough), but it could also be due to unrelated factors, like kaliope said.

It is hard to categorize, but can you think of some areas in which you've had difficulty significantly lower/higher than your baseline level of ability with keeping things in working memory?

For example, I have decent semantic memory (knowing a basic summary/outline/description of things that happened to/around you). If I'm reasonably certain of a semantic memory, and I have the opportunity to verify it, I usually find that I'm remembering it right. If I have a solid semantic memory of something, I also seem to remember what emotions I felt about it pretty well, for what that's worth. But then there's my nonverbal (i.e. "sense") memory of the actual experience. I can't "play back" those physical sense memories of things that happened. I can't "see" it again in my head, even though I know (semantically) exactly what happened. (e.g. I suspect my visual memory in particular is like the equivalent of me having a blurry old photograph where most people would have a short video clip.)