Q: What would happen if the AC compressor bearings disintegrated while driving 65 mph?

My father took my inherited car to mechanic in Phoenix AZ. back in December of 2013 with a concerning noise under the hood. The invoice says 'customer concerns: metal on metal sound from the right front.' The synchronized has been replaced in this invoice. After that, for the next 3 years my father kept trying to conserve the AC compressor by not driving the vehicle that much.

Now that I own the car, I'm trying to figure out what might happen if the bearings get so grinded up that they turn into metal pieces of sand?

So far, the vehicle runs good except for that metal clanking noise. Mostly it is heard while at idle and low speeds, that's also after the belt squealing stops. Yes there are two different and distinctive noises.

My car has 77416 miles.
My car has an automatic transmission.