[relic]

Are these the original wheels and tires or was there a swap?

If the answer is ‘no’ and the tires have worn on the inside only then it is an alignment problem. Either too much (negative) camber or too much toe out.

For it to be on both sides strongly negates it being the result of a pothole and sounds very much like someone misaligned the rear.

You say it is an ‘ex BMW’ car so the problem is what might have been done before you got it and just what warranty it still has.