TCC/LE was released WAY before Windows 10 (that is still not released), and Microsoft apparantly broke the version API, the latest TCND 18 has a workaround fix that makes the ver work correctly under Windows 10, I'll let Rex comment on if he's going to fix this one command for TCC/LE
Flashing back to MS-DOS, which had an API to report the DOS version... and a device driver to lie about the DOS version... and another API to report the real DOS version; and of course DR-DOS had its own DOS-version API, because it pretended to be PC DOS on both the documented APIs. Wheel turnin' round and round, you go back, Jack, do it again....
At least this time round there isn't one single list of programs and version numbers to lie about, if you setup your application manifest correctly then windows will report the correct version to you. If you haven't released a windows 10 compatible version of your application then lying to you and pretending to be a version of windows that you do support seems like a reasonable compromise.
My OCD side thinks it shouldn't lie, but I understand the practical reason for doing it and putting in a ReallyGetVersionEx would undermine it.