If there isn't much piracy then there aren't many purchases (often none) so there's no justification for an extension.
But earnings themselves aren't a justification, it's the public good that comes from the further works you create while striving for more royalties that are the justification for this expensive and wasteful bureaucracy.
And there's no reasonable argument for 150y copyright, but the very stories copyrighted (Snow White, etc) are a powerful argument against copyright at all. With modern copyright on the works they borrowed, Disney never would have existed - unable to pay for access to cultural heritage.
But earnings themselves aren't a justification, it's the public good that comes from the further works you create while striving for more royalties that are the justification for this expensive and wasteful bureaucracy.
And there's no reasonable argument for 150y copyright, but the very stories copyrighted (Snow White, etc) are a powerful argument against copyright at all. With modern copyright on the works they borrowed, Disney never would have existed - unable to pay for access to cultural heritage.