It is not just sparc, sparc design is open right?
Yes, SPARC design is open. Anyone can license it. Buying a SPARC license is $50 US Dollars.
If China had any interest in SPARC they could afford the cost of the $50 SPARC license. But they didn't.
If anyone thinks that China isn't able to build their own supercomputers based on their own technology, think again:
https://en.wikipedia.org/wiki/Sunway_TaihuLight
That is the world's current #1 supercomputer. The chip architecture is homegrown and home cooked in China, and evidently a state secret. Some people speculate it's based on DEC Alpha, some others that it's based on ARM64, some other others that it's MIPS.
The world's #2 supercomputer is the Tianhe-2 and is based on Intel Xeons:
https://en.wikipedia.org/wiki/Tianhe-2
Sorry SPARC fanbois, SPARC ain't where supercomputing is at. Get over it.