Why is bitcoin falling? the long-term bitcoin holders would be selling their bitcoin for fear of an attack with quantum computing that could happen within a few years, for this reason they would be anticipating to get their profits before it keeps falling further? .. the fact is that bitcoin will not return to the price levels of December 2017
What makes you think that quantum computing is anywhere near a point where it can make an attack on the ECDSA part of Bitcoin? Even if that is the case people should have enough time to know in advance so that the developers can prepare alternatives to incorporate that are more resistant to quantum attacks.