How Feasible is the Planetary 'Safety Net'?

A group of scientists have put together a 'safety net' to protect the planet from the interdependent challeges of biodiversity loss and climate change (https://www.theguardian.com/environment/ng-interactive/2020/sep/29/planetary-safety-net-could-halt-wildlife-loss-and-slow-climate-breakdown-aoe). They have simply added together 1. The exising protected areas; 2. Unprotected areas that are home to rare species; 3. Areas that house distinct clusters of species; 4. Areas where the largest mammals (that often follow long-distance migrations) live; 5. Locations having the most intact ecosystems, least disturbed by human impact and 6. Areas that should be added to prevent further climate breakdown. The whole total comes to a fraction over half of the Earth's land mass and it overlaps with the world's largest natural carbon stores. They note that their ambition is greater than the current 30% of lands and oceans is advocating. They deem the UN figure inadequate. I think it's a nice idea (if, a bit land and large mammal orientated) but I feel that the authors are wildly optimistic when they suggest that the plan could (because the UN is 'too slow') be pushed through by collectives of environmental scientists, indigenous leaders and Greta Thunberg's, showing the old folk how to 'get their heads around it'. Don't they realise how concerned about themselves and their immediate families people can be? I expect there would be considerable resistence in many locations from politicians, environmental exploiters and ordinary people who live where i is hoped to create the safety net.