adding to this, i'd say it's actually a generally more useful term precisely because it's not medical.
Medical diagnoses have all these maddening arbitrary qualifications like needing to display 7 of 9 symptoms and whatnot, which means that if you only have 6 symptoms then you can eat shit and don't get proper help for the struggles you may face.

Meanwhile if you have neurodivergent traits that noticably affect you, then you're neurodivergent. Bam. Done. It's the same kind of term as "handicapped"/"disabled", you clearly know it when you see it and there isn't much to argue about beyond what the person in question feels comfortable being labelled as.