I think you might have something there - I'm also thinking of the children we sometimes call 'old souls' or 'old head on a young body' - I was one of those, not overly interested in 'kids' stuff' and liked talking to much older adults to hear their stories about life. I liked watching The Sky At Night. I could remember very detailed stuff about some not so interesting events (and still do).
There were/are many of us about! The teachers at my primary school mentioned to my mum about me possibly getting a grant to go to a private boarding school for secondary education as I was so 'forward' in some things - but I was too fearful and already knew my mum wouldn't be able to afford the uniform and transport.
it was a bit odd being like me I thought - at the age of 8 I could read at the age of 14+ but no-one had showed me how to use a dictionary yet, so when a teacher asked me to find a word in it I had no idea. I ended up crying because I didn't want to get told off (not that I would have been, my teacher was lovely). I had the ability but not the context or comprehension of context, yet.
I have also self-identified as 'on the cusp' of ASD at the age of 51 - now waiting (very contentedly) for the NHS to get around to me. Lots of things make a lot of sense, now.
**edited to add: My Godchild is also a bit of an 'old soul', which I love! They answers the telephone with "good evening/morning/afternoon Aunty J, how are you?". They're 11. They also like trains, machines, building sheds and other wooden creations and camping out.