Sixth Tone was setup by the Chinese government to be more relatable to western audiences by sounding more critical, so you shouldn't take it at face value. On the other hand, it does provide useful information, and it could be seen as an attempt to provide higher quality news out of China.

After the Xi era, I think Chinese propaganda will actually move in a more critical/informative direction like Sixth Tone, since the current overt methods are losing effectiveness. But again, that could also just mean real reporting depending on how the government evolves.