Unfortunately there is nothing to do, bitcoin can be bought by anyone, in fact I would be surprised if governments have not accumulated bitcoin in secret for years, this is why despite the brilliant and advanced technology made by satoshi we still depend on the financial IQ of the average person, if they cannot understand why something like bitcoin that is scarce and that cannot be printed at will and in any amount desired by the governments is superior to fiat currencies then the future of bitcoin is not going to be as bright as we think it could be.
This! Absolutely, I am sure governments own Bitcoin as well. For almost any government a billion or even half a billion is nothing. Why not buy some of that chap junk and see what happens later on. I believe a lot of governments bought into Bitcoin long ago.
Governments do not even really need to buy bitcoin since they can even confiscate it, there have been cases in which governments found themselves with huge amounts of bitcoin after coming down to one of those dark markets that exist on the dark web, supposedly they sold those coins but what if that was just a front and instead they kept hose coins? Then that will mean that many governments are already in bitcoin preparing for the next financial crisis they caused on the first place.