If I were looking to assign blame, I'd start with the coal and gas operators who are digging up fossil fuels that would otherwise remain in the ground just to fuel their bitcoin mining rigs, those who peddle specious arguments claiming that it somehow isn't a problem, those who turned the whole thing into a machine for separating the gullible from their money, and those who've built the shaky, buggy, mostly proprietary, convoluted, half-finished, untrustworthy, horrible mess that is the software ecosystem surrounding the whole cryptocurrency sphere. Perhaps none of that could have been foreseen by whoever designed bitcoin. On them we can instead put the blame for the failure to make it anywhere near sufficiently scalable, and the ridiculous choice of mechanism for the bitcoin monetary policy which serves to make it function only as a get-rich-quick pyramid scheme and not a durable currency. Regardless of who's to blame, it's got to go.

Perhaps there's already an alternative out there somewhere which is actually useful and not based on avarice, fraud, unsustainable resource usage, or unsustainable hype, but if so it's currently hidden under such an enormous pile of shitcoins that it's impossible to identify. At least the internal combustion engine was good at doing the thing it was supposed to do.