I don't see why this would invalidate the concept of physical keys.
The problem of visual key copying can be easily solved by either making keys in a shape that doesn't allow to see the ridges easily (something like 'E' with middle bar being the actual key) or by making a "dynamic" key that changes shape after you insert it into the lock.
The problem of visual key copying can be easily solved by either making keys in a shape that doesn't allow to see the ridges easily (something like 'E' with middle bar being the actual key) or by making a "dynamic" key that changes shape after you insert it into the lock.