Altcoins, even Bitcoin is not fully anonymous. Its semi-anonymous. And this is why if you control the gates and control the amounts of fiat currency swapped for cryptocurrencies you can track, from that point forward, the route the flow of value takes.
Make no mistake. Governments see cryptocurrencies as a coup détat against the international banking system. And if you own or trade cryptocurrencies, you are viewed from the establishments point of view as taking something that is not yours to take autonomous control of your wealth.
In 2018 cryptocurrency demand was choked. As Bitcoin supply overwhelmed demand, the price of Bitcoin and other cryptos fell while the big players were quietly accumulating a position.
I think you are hitting on a popular conspiracy theory as the reason why govenments may want to go against cryptocurrency. The fact remains that the government is aware of the good sides of crypto but there is still a lot that needs to be put in place to ensure that people don't lose their money easily due to volatility or worse still, cyber hacks. These are issues that need to be sorted for regulation to come in