Quantum computing is a reality today, it is just a question of how many qubits can they stabilize. They were at 128 last I checked. Once they get into the thousands they can start pwning GPG. I hear that they will likely be able to make a significant amount of progress in a relatively short amount of time, and that the rate of stabilized qubits will rapidly increase. There is a quantum resistant asymmetric encryption technique that seems to be getting a lot of attention recently called multivariate public key cryptography. Using larger key sizes increases the number os stabilized qubits required, but that wont matter when they start exponentially increasing the number of qubits they can stabilize.