Why do governments cry so much about crypto?

I have had this question since I live in a country with no Crypto taxes. Considering what the Politicians, the SEC and the bankers say about Cryptocurrencies, it should be pretty clear that Cryptocurrencies hold NO value whatsoever. They consider it to be a worthless and useless asset.

If that's true, then why do people have to pay taxes on Crypto? People should not be paying any taxes for holding a useless asset. The same politicians and government bankers who call Crypto worthless receive a part of their paycheck from taxes collected from Crypto. It is clearly hypocritical to tax Cryptocurrencies and profit from it while calling it worthless at the same time.

Thanks