Yeah, China doesn't like to play with open cards. Which has its disadvantages, not only for China's opponents, though.
If i only could find those old sources that shed a light on the China sells, but i failed until now.
EDIT: Still, there are articles covering the China selloff (2019, by the way).
According to CryptoQuant CEO Ki Young Ju, blockchain data shows that the seized Bitcoins were moved through coin mixers, a process typically used to obscure transaction trails, and subsequently deposited into centralized exchanges, including Huobi, in the latter half of 2019.
This movement suggests that the assets were liquidated soon after the seizure, in mid-2019, rather than retained by the state as part of any long-term reserve strategy. Although China is often listed among the top countries holding Bitcoin, the available data indicates that these holdings may no longer exist in government-controlled wallets.
The PlusToken case illustrates a broader challenge in estimating national Bitcoin reserves where seizure does not always equate to strategic accumulation. Without public reporting or wallet transparency, assumptions about government-held crypto remain speculative, especially in jurisdictions with limited financial disclosure.
https://www.ccn.com/education/crypto/us-vs-china-who-holds-more-bitcoin-and-why-it-matters/
Okay.. makes absolutely sense although the assumption still stands