Quitting a stable job may be a bad idea given the current situation in the crypto currency market. The market is red and coins are constantly losing their price. Probably the best option at the moment is a permanent and stable main job and working with crypto currencies in your spare time.
I don't think current market state have anything to do with quitting the main job. If market is good now and quit, then what is going to be in couple of months when market goes down? Current market state is irrelevant, because market is shifting gears and directions.
Quitting is bad idea if one does not have substantial mount of cash for rainy days.