There is a current Planning system discontinuity as to when and by whom Sites are selected and potentially approved for development, both Regional and Local.
In practice there is an administrative vacuum as to who actually appraises landform for preferred retention as natural, or suitability for urbanisation? For instance – who professionally assesses and reports on the long term value to the community for various purposes of sites and adjacent conditions to the community.  (WAPC doesn’t do this, but expects Local Authorities to do so, but most of them do not have professional resources for this).
Commercial developers, to whom reserving any natural areas and outdoor spaces for community use is viewed as a financial ‘hindrance’, often find ways to bulldoze them absolutely clear and featureless first -as flat as possible -or pretend they are making a contribution to environmental conservation by employing wild-life experts to remove all fauna – before then clearing the land and their habitats altogether!  So, much of value that could be managed for amenity as public park land is being needlessly destroyed.