It doesn’t, what you’ve got is either a device that was sufficiently waterproofed (Which maybe aren’t AirPods waterproof?) and just needed the liquid to clear out on its own

Or a device that’s working on borrowed time, the minerals have still been deposited on electronic components after the water evaporated on its own. Devices can take some shorting here and there, but it’s only a matter of time before it becomes too much. Could be a few days, couple of weeks or even months and then POOF dead for good