Not all protection causes harm to the public domain --- protection can IMPROVE the public domain

(Graham J. Reynolds University of British Columbia (UBC), Associate Professor, Faculty of Law, “The Precautionary Principle and its Application in the Intellectual Property Context: Towards a Public Domain Impact Assessment,” pg online @ https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2347922 //pa-ef)

This is not to say that increasing intellectual property protection always (or ever) has a net benefit on the public domain. While increasing intellectual property protection may act as a further incentive for the creation of new expression, it also expands protection for existing works. Thus, although expanding intellectual property protection, for instance by increasing the term of copyright, may result in new works being created (making certain uses of those works, such as fair dealing, immediately available as part of the public domain), it also extends the period of time in which other uses of existing works will not be available as part of the public domain.