I always wondered why artists in this situation couldn't just re-record and re-issue the work (and ideally retain the rights in the new work). Obviously there's fresh costs involved (multiplied if you're not a soloist), but modern recording equipment and techniques have got so much cheaper and widely available that excellent results can be achieved with a bit of ingenuity (and work!) - instance the amazing explosion of wonderful lock-down music in the last year. Distribution and reward for the work is quite another problem.
Ross