1. The volatile nature of Bitcoin.
2. Lack of true value and backing.
3. Financial crime.
4. Cybersecurity Risks.
I don't believe that these points are genuine reasons why governments are not adopting Bitcoin as reserve currency.
Without the volatility of Bitcoin, it will not be profitable. Anybody who understands Bitcoin can take advantage of the volatility to make profit. Nations like El Salvador and Bhutan are making money from Bitcoin because it is volatile.
If you think Bitcoin don't have value and backed by physical asset, is the dollars backed by gold or precious metals? The dollars is just a printed paper yet nations are keeping it as reserve currency.
Fiat can also be hacked or stollen. The rate of bank hacks and fraud keeps increasing every year. It is not only Bitcoin that suffers from criminal attacks.
Cybercrime is affecting all the sectors of the economy. The systems of many governments and top businesses have also suffered hacks..
5. Influence of Global Financial Institutions.
Institutions like IMF, World Bank, and BIS no really dey support Bitcoin so countries way dey dependent on these institutions for loan and aid go always avoid to adopt Bitcoin reserve in other to stay for there good book make them fit they give them loans and aids.
I will accept this as an important reason. IMF will have full or partial control of the economy of nations that are indebted to it. It was IMF that made El Salvador repel some of the laws that made Bitcoin a legal tender. The financial organization is also questioning Pakistan for allocating electric power for Bitcoin mining.