VOA also have a Learning English spec for broadcast english [1] but that seems to be a lot looser of a spec.
So it's definitely not impossible. The funny thing, is I remember being told in grade school that in English Canada, I was to write numbers with a space as the thousands separator. `$10 000.00`, instead of `$10,000.00`. This is because french Canada uses a comma as a decimal point, `10 000.00 $`, so a space is non ambiguous. I have rarely ever seen the English space format in use here. I don't think English speakers would respect any authority if it wasn't as domain-scoped as Aviation or Learning english.
[0] https://www.asd-ste100.org/ [1] https://en.wikipedia.org/wiki/Learning_English_(version_of_E...