I don't think there is a single true answer to your question, 10googol. People on the spectrum are just as different from each other as NTs are. I reckon many of us focus on different things and neglect an individual range of other things.
As far as I can tell (it's still a voyage of discoveries, even at my age), my focus is with living things a lot of the time. In the zoo, I am usually the first to spot the tiny frog in the large terrarium stuffed with plants whereas all my NT friends still spend a full minute trying to spot it after I pointed it out to them.
On the other hand, I am often awful at getting the details of a practical assignment and then I have to work my way through it until I find the right solution by trial and error, like when I was trying to assemble a night stand for my grandmother and found that the drawers wouldn't close because I had slid in the screws from the outside of the drawer rather then from the inside.
For other people the focus might be with something completely different, so I expect you will be getting a lot of very varied answers here.
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