The threat is in the form of increasing global warming which results in climate change. Generating Bitcoin requires a capable computer to solve complex mathematical puzzles and high electricity consumption. so that some countries prohibit mining for several other reasons such as in China and Iran some time ago. if so will bitacoin and others be able to run forever or is this just an excuse to change the green field to red..
The power consumption of bitcoin and cryptocurrency miners are negligible which doesn't even comparable to a small country's total consumption, but we are the people talking about global warming and energy consumption while sitting in a air conditioned room, how hilarious isn't it.
