As soon as Quantum computing becomes cheap enough all hell is going to break loose when it comes to public key cryptography.
I've heard people say this before, but can't we just add more encryption bits? True, 256-bit, 512-bit is too low. What about a million bit encryption? Quantum computing will only be a problem if just a few people have these computers. If they are mainstream then there is a level playing field once again.
it is not question of adding bits,
but question of practicality. you can encrypt your message 100s of times with diff ciphers, each time use different password not less then 90 characters and your message will be "Hello John !!"