They are making the free upgrade from Windows 7 and up globally, but this article seems to imply they are going to make an exception for China and make the upgrade free for all Windows users.
The title does seem to imply that. What the article in fact says is that the free upgrade is being offered globally, but the motivation behind it is to re-engage with Chinese Windows users who have an unlicensed OS.
That makes sense, given XP can install and run decently on a machine that would choke on Windows 7, if it would even install. Minimum system requirements are still a thing, and as light and efficient as Windows 10 is, it's not meant for 2001 era technology.