> But different autistic people struggle with different things, in different ways.

Different asthmatic people struggle with different things, in different ways too, but it's useful to have a general diagnosis umbrella to cover those who have asthma even though symptoms and effective treatments may vary.

Work is ongoing to get better defined categories for autistic people, but for now at least we've got a category for people that match a broad set of traits/symptoms/challenges to work from.

The problem is that the set of problems is very broadly defined, changes over time, varies from person to person, it's often impossible to obiectively test.

Can't it be that a neurotypical person is bothered by some autistic triggers? Would that make them neurodivergent? How many of those triggers do you need to have to be under that umbrella? 1? 5? 20?

It is indeed called a spectrum, and I think it gets so fuzzy at the edges that the only way to define where it starts or ends is purely arbitrarly chosen.