I don't think you understand how modern naval mines work. In relatively shallow waters, bottom mines can be employed, which are not visible on sonar, and they use a variety of sensors so that it is incredibly difficult to trick them into detonating. Others burrow underground at higher depths still and then fire a torpedo at passing ships. So generally modern mines have to be disabled one-by-one, and without firing on Chinese forces, the Chinese would be laying more mines than the US Navy can disable. It will definitely take weeks if a path is ever completed.

Even fairly primitive mines in relatively smaller numbers (scarcely more than a thousand - China has at least 100,000) in the Iraq War were able to score a mission kill and a major hit on US ships. And that was without US ships actually docking in Iraq.

Do you know how long it took to sweep just over 1000 of those quite primitive mines in Iraq? Around 3 months.