Is Big Sur 11.0 and 10.16?

The version returned by macOS Big Sur depends on the SDK used to build the application. Is it official that Big Sur is both 11.0 and 10.16?
You have probably rad this. Don'y know if that can be considered an official confirmation tho

https ://eclecticlight .co/2020/07/21/big-sur-is-both-10-16-and-11-0-its-official/

or this more rectnt:
https ://www.reddit .com/r/MacOSBeta/comments/hn0k3f/whatisitnow1016or11/

Apple says: The system ProductVersion is reported as 11.0 only on the Developer Transition Kit at this time. Existing Mac systems will temporarily report the value as 10.16.

Yes I read the first link, but I did not find anything from Apple.
I am wondering if it can be considered valid to recognize Big Sur as 10.16 in any systems running Big Sur (I mean when it is released).
Big Sur is 11.0. But if the app was compiled with a previous sdk, it will report "10.16" to avoid breaking some wrongly coded apps version checks.

I see this as a shortcoming of Apple engineering, trying to patch the OS in order to let buggy old software that assumed MacOS will remain X (10) forever continue running. This is more MS-Windows than MacOS, and I wish versions were the only aspect of this.

What I'm concerned with, however, is the opposite - out software is deployed on both older and newer systems, and needs to report to server the MacOS version it runs on - and we're having Big Sur appear sometimes as 10.16 sometimes 11.0 --- calling the same API!

No, we can't align all our build-tools to MacOS SDK 11 - since on older systems we use APIs that are now deprecated on new OS versions, so we maintain older build machines for deployment on older Macs.

What I seek - is a way to CONSISTENTLY get 11.x from MacOS Big-Sur, for ALL our versions running on ALL Macs and MacOSs

With all that wonderful and so-elaborate Info.plist thing - why can't we have 10.16 .x for SDK version and 11.x for "Marketing version string" ???

Is Big Sur 11.0 and 10.16?
 
 
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