The US government selling bitcoin will never cause the market to crash and that's obvious. But what I find strange is that the bitcoin market is worth more than 1 trillion USD and the total market capitalization is almost 3 trillion USD. But why every time just a few billion USD (BTC) sold at the same time can cause a decline of 5 to 15%, it is difficult to understand because 2 or 3 billion USD is very small compared to the trading volume and as marketized capital.
Take two half a litre glasses that are 2/3 full, and move 1/10 or 1/5 of the water between them.
You can move like a million litres, that is the volume, but what happens if you try to dump an additional litre into them? They both overflow.
So despite being able to move back an forth 1 million litres, just one poured without 1 taken out made them overflow.
That's the difference between value and market depth.
Look here:
https://coinmarketcap.com/currencies/bitcoin/BTC/fusd volume is right now 5 billion, but it would take only 4 million to reduce the price by -2% (market depth).