Pianos neglected long enough will eventually fall into a state of disrepair where fixing it would cost nearly as much as making a new one. For a rare vintage valuable vintage piano it might make sense to restore it, but several million pianos have been made since 1900 (the US alone bought some quarter of a million pianos in the first quarter of the 20th century) and it would be unrealistic to restore them all. This fate is far preferable than the dump.
