If the killer app of the Blockchain is Bitcoin, what does it say about the underlaying technology that the "killer app" is useful only as an extremely volatile speculation vehicle, and an ecologically disastrous one at that, with a tertiary use case of paying for illegal goods and services?
It's not good for crimes because Chainalysis can track the coin movements afterward - though maybe it's good enough. And porn doesn't seem to use it, maybe because the transaction costs are too high or it's too unethical even for them.
And it's not good for speculation because it turns out it's just correlated to US tech stocks.
This is the use case mentioned. The OP is saying that everything else about it is useless.
Having the option to do something illegal should the need arise is a benefit to some people, and government control of the financial sector is not beloved by everyone.