Variables such as temperature of qubits, voltage and time of laser pulses can be changed. The arrangements of specific quantum gates can be varied as well. Unlike an ASIC, quantum computers can be reconfigured from time to time to fit the required algorithm.

For now, quantum computers are far from general-purpose, and even then it will be redelegated into a discrete "QPU" card similar to your GPU for quantum-related computing purposes.

Affordable room temperature and pressure superconductors will need to be mainstream before that happens.