People make up the government right? Yeah, and if you enter the bitcoin market, there are always sell orders and buy orders, those sell orders and buy orders did not place themselves, they were placed by people, real people like those in the government.
So, if a government decide to sell their bitcoin when another government is deciding to buy and hold bitcoin, it's their both and individual decision, same way you can decide to buy some bitcoin while I myself may decide to sell mine instead for our respective reasons.
Market needs to have buyers and sellers, from institutional, governmental to retailed investors and traders. If there are only buyers or only sellers, the market is done and dead.
The German government possibly have a reason why they decided to sell off their bitcoin, and if the government of Bhutan decided to invest in bitcoin, they also have their own reason as well, there ain't anything odd here because the crypto market is always in "soldier go, soilder come" mode, which means, as an investor is leaving, another investor is coming in, simple as ABC.
German government is not matched for this example and in comparison with Bhutan government. These governments got bitcoin in different ways, with Bhutan it is from their investment through mining and with Germany, it is from seizure of bitcoin from criminal crack down.
German government is like the USA. government and other governments that got bitcoin not from their own investment decisions, have very little reasons to hold these bitcoins.
https://bitcointreasuries.net/