My recollection is that MS did confirm that Windows 10 was chosen for some vague mention of technical reasons, which most people latched on to as being explained by the "Windows 9" check.
I have seen code in the 2010s that did explicitly check for "Windows 9" as a means to check if it was running on Windows 95 or 98. That doesn't mean that the code would actually work on those systems (it could well be a prelude to saying "your system is too ancient, we don't support you"). But such kind of cruft tends to last a very, very long time without active maintenance.
I have seen code in the 2010s that did explicitly check for "Windows 9" as a means to check if it was running on Windows 95 or 98. That doesn't mean that the code would actually work on those systems (it could well be a prelude to saying "your system is too ancient, we don't support you"). But such kind of cruft tends to last a very, very long time without active maintenance.