At least on Windows 10, it doesn’t follow my OS settings. I’ve for example set:
dd.mm.yyyy
hh:mm
But it shows me in my properties the US date/time format, including am/pm. I don’t seem to be the only one with this behavior (see this thread).
Besides this, I share the opinion, it should be possible to set it independently of the OS settings anyway.
A workaround is described here, but that’s that’s ugly to keep dates as a text format.