The world of technology is evolving every year what if in future a new tech is been born that can kill crypto or works better than crypto won't this kill cryptocurrencies?
Also I heard that super computers can get through all crypto wallet keys easily in a matter of days, true or false?
When super computers become that advanced, crypto will simply move on to a new stronger algorithm. It is all based on math in the end and the power of computing has limits no matter how fast they become. You just throw a few more zeros at the end of the equation and those new computers won't be able to hack it anymore. If those computers become that fast, you'll have many other problems anyway. Your bank accounts, your passwords all will be gone instantly. So, don't lose your sleep over it.