Leitz did not use the Zeiss hard (or similar) coating process for some time, they used a softer coating process, and some of the optical glass types they used were soft.
Don't think Leica went to a hard coating until '50-60...
Many type I Summicrons and 3.5 Elmars are badly scratched, but if you use a hood this is not terrible unless you are a collector. The area of scratches is small (normally)... The collectors put a large premium on boxed kit, waste to take it out and use it...
If you are a shooter most people use a CV LTM or M lens anyway, if you wanna collect pay the money, if you only want to shoot dont.
Ive touched the asph apo 5cm, nice lens, but could you tell the photo was taken with one?