That is, for lack of a better term, a "Microsoft-ism"; in MS documentation, "ASCII" consistently means "single-byte or MBCS" and is interpreted relative to the current codepage, as opposed to "Unicode" which means "UCS-2 or UTF-16". You can also see examples of "Unicode" in the docs you link to.
Not sure if I've ever seen a Microsoft doc do it, but many other places including articles be MS "MVP"s use ASCII and ANSI interchangeably.
In MS output in my experience consistently means standard 7-bit ASCII.
Things they routinely do oddly are using ANSI to specifically refer to the WIN1252 code page (a superset of ISO8859-1 otherwise referred to as CP1252) when the institute of that name did not define nor dictate user of the codepage, and including (or requiring for correct interpretation) the BOM sequence in UTF-8 encodings when the standard allows recommends against a BOM in this context.
> That is, for lack of a better term, a "Microsoft-ism"; in MS documentation, "ASCII" consistently means "single-byte or MBCS" and is interpreted relative to the current codepage
I've read my share of MS docs and I do not recall ever seeing this to be the case. Like the parent says, I've seen "ANSI" used to refer to that, not ASCII. Do you have any examples of where they say "ASCII" where the intention is obviously something broader than 0-127? It makes me wonder how I've missed this if that's the case.