I don't think it will reach 20k again in the next 3 years. Something up to 15k is reasonable to expect. It will be great, cryptocurrrency and block chain will be the greatest until they get replaced by something better. I believe that it will not happen in the next 5 to 10 years, so we are yet to witness the greatness from BTC. Look at it as the best project made so far, the best technology built so far. How can you even consider that it will cease to exist in the next decade?