They are trying to own the whole bond market.
If we thought that staking assets that are already staked were crazy crypto DeFi inventions from the last 3 years, we now know that "TradFi" has done it all before.
There are no new things in this world. Everything has happened before says King Solomon.
Absolutely, the Bank of Japan is the sole buyer of Japanese bonds. There is literally no market for them, they're only maintaining the illusion that that debt is worth something for someone.