Interestingly, Shenzhou isn't a Soyuz derivative -- it's significantly larger and has other divergent features (its orbital module can allegedly stay docked to another vehicle even after the crew capsule detatches for re-entry).
As I understand it, China is excluded from treaties governing cooperation in crewed spaceflight that go back to the Apollo-Soyuz link-up and include other third parties such as ESA and Japan: this locked them out of the ISS program. So they had to develop their own space station, too.
You could say it makes the original statement unintentionally true.