Because it is wasteful by design and gets more wasteful as it scales. Transaction fees are onerous and transactions themselves are excruciatingly slow. Then the deflationary nature of cryptocurrencies makes them terrible currencies. It makes more economic sense to hold them than spend them.
The rare events where their use doesn't involve crime are overwhelmed by the criminal uses.
>Because it is wasteful by design and gets more wasteful as it scales
Plenty of other things are wasteful by design, like military for example. The more military things we build, the stronger we'll be. Same with BTC hashrate, the more power the stronger the network.
Fossil fuels are used to make just about every thing you touch. That's the opposite of waste. They're utilized. They can't be replenished but they're certainly not wasted.
Things being so cheap due to fossil fuels that you buy new things instead of fixing them is wasteful. And there is value in CCs, even if you personally don't find them valuable. They money that is zero trust, private, and eliminates some mechanisms of manipulation (inflation). Let's not forget that bitcoin grew out of the financial crisis and the mismanagement of monetary policy leading up to it.
