Who decided the idea of spacing for numbers of 1 Thousand & above?

Who decided the idea of spacing for numbers of 1 Thousand & above?

I think '1,000' is acceptable - but '1 000' is totally strange to me.

I can guess I am very British when it comes to indicating numbers.

Aidan.

Didn't we just go through this without any resolution?
https://en.numista.com/forum/topic109466.html

I think this became standard with the new guidelines:
https://en.numista.com/forum/topic109017.html