The issue isn't that crypto-currencies or blockchains don't have potential uses when done right, the issue is the completely arbitrary and nonsensical junk "economics" behind wasting hundreds of billions of $ in energy costs over their lifespan on the back of hyper-deflationary money-printing is almost completely divorced from reality of the real-world economy. The purpose of a currency is to be stable. That's why China under-pegs the Renminbi vs the USD to give its export economy stability. Conspiracy theorists ranting about the dollar "hyper-inflation", the Rothschilds, etc, sound edgy until you stop measuring BTC in "evil fiat" USD and start measuring it in tangible commodities, eg, the price of BTC measured in iron, copper, gold or wheat over the past decade, Bitcoin 'economics' falls apart even harder vs the inflationary "fiat" it's supposed to "cure".
Imagine being a baker seeing the price of bread in Bitcoins change from 2 to 0.002 in the space of mere months when literally nothing about the demand for bread, bakery operating costs, supply of wheat, population size, etc, is changing more than +/-5%. Pretend the USD doesn't exist, and there's only BTC vs Bread. What has "changed" outside of a speculative 'currency' bubble? Nothing. Imagine there was no USD but instead $50 oil was set to 50BTC at 1:1 10 years ago and all fiat disappeared leaving only native BTC, do you think after 10 years that BTC pricing equivalent of $0.001 per barrel is a "fair price for oil" bearing in mind it still cost a few thousands times that to actually produce? Even ditching currencies altogether and going back to bartering gives more pricing reliability.
The current bubble "values" are completely worthless vs actual real-world product pricing / trade, which is why almost nothing (except Ransomware) is priced natively in Bitcoins and the whole bubble driven by circular logic
"We're buying BTC because it's valuable and it's valuable only because we're buying it" aka Tulip Mania 2.0. What a few geeks who are great at explaining Blockchains but extremely cr*p at economics really want with this stuff is a digital get-rich-quick scheme, but keep trying to dress that up to be some world changing utopia it simply isn't. The reality of the "decentralized" currency is that
95% of BTC are controlled by 2% of people and 70% of BTC wallets have less than 0.01 BTC in them. So in the end, it's ended up no different to "evil fiat" for rallies & bubbles being massively manipulated by a few on a whim except that a few "whale" investment bankers have replaced the Fed. Massive environmental damage (the cheapest electricity in China, Russia & Iran fuelling the "farms" are almost entirely fossil fuel driven) and the train-wreck left behind on PC hardware market are just icing on the cake of absurdity.