Disclaimer: I have no quarrel with the mods using the term in the creation of this community. I understand why they chose it, as even if they share my disagreement with the term when applied to ADHD, there's not really a better inclusive term. "Mental illness" is really the only other option, and naming a community that would probably invite darker discussions that the mods might not be prepared to handle.
Another disclaimer: I think the term is perfectly valid when applied to autism, as autism is not, to the best of my knowledge, a mental illness so much as a difference in processing. Being autistic is only "bad" in the sense that our society discourages autistic traits. (Apologies if this is wrong; I'm neither autistic nor especially knowledgeable about autism.)
The term "neurodivergent" implies that there's nothing wrong with you if you have ADHD--you're just special and different. But my ADHD is an illness that requires treatment. A lot of people will tell you that the only reason ADHDers struggle is because society is set up wrong, but I don't think that's true, at least for me. Being unable to remember anything, unable to self-start, and hypersensitive to rejection would be massive problems in any world. Sure, the world today is particularly brutal for ADHDers in a way we could probably mitigate if we reorganized society to be kinder, but that doesn't mean ADHD isn't ultimately a disorder that some people need to treat with medication and therapy.
I realize this is like 2 months later, but I read your posts and wanted to let you know about an online event/community called NaNoWriMo (National Novel Writing Month). It's an annual event/challenge (traditionally in November) to write 50k (or your own goal) words in 1 month, with an explicit quantity > quality approach. I'm an aspiring writer in the same boat as you and participating in NaNoWriMo is the only thing that ever worked to get me putting words on paper, even during college. It provides some structure (daily or weekly goals) without being suffocating, and it adds a bit of a gamification/friendly self-competition element to the experience of writing, but the community itself is really laid-back, casual, and inclusive. There are also sometimes in-person writing get-togethers that can be very helpful to get that extra dopamine boost for writing. If you've already tried out this or something similar and it wasn't for you, no biggie, I just wanted to highlight a potential writing aid that you/others reading might not have heard about.