Native equals "not requiring some weird emulation layer", and it matters because of performance, maintainability and quality.
Got any quantifiable data that shows Git suffers performance-wise on Windows? No?
MinGW (unlike Cygwin) is not an emulation layer, any less than libc is. If you're operating by that level of pedantry, you'd be hard pressed to find any
"native" Windows software, since pretty much everything depends on the Win32 API, which isn't native.
The mind boggles at the doublethink required for you to be able to call Python "native".