Disney are only willing to pay an appropriately large amount of money to keep their IP if they believe the public are actually willing to pay them significantly more because they have that IP.
It's not such a big deal applied to films; the amount in the government coffers is swollen by less than the extra Disney fans have voluntarily spent on old films, but no great loss is suffered by those who aren't willing or able to pay Disney's asking price. But establishing a principle that corporations should be able to retrospectively extend the fixed-term of their IP for cash would be particularly dangerous when it comes to things like patents...
It's not such a big deal applied to films; the amount in the government coffers is swollen by less than the extra Disney fans have voluntarily spent on old films, but no great loss is suffered by those who aren't willing or able to pay Disney's asking price. But establishing a principle that corporations should be able to retrospectively extend the fixed-term of their IP for cash would be particularly dangerous when it comes to things like patents...