This is an interesting article describing 10 myths about the Green Belt from the CPRE.
Myth 1: Green Belt is an old fashioned idea and it’s time to pension it off
Myth 2: Green Belt is sacrosant and safe from development
Myth 3: Green Belt protection pushes house prices up
Myth 4: Green Belt has little or no environmental value
Myth 5: Green Belts only benefit people who own property within them rather than the wider public
Myth 6: Just building on a small proportion of Green Belt would leave us with more than enough
Myth 7: If we don’t allow development in the Green Belt, people will leapfrog it and commute in an unsustainable fashion from elsewhere
Myth 8: Green Belts have the effect of confining the urban poor to live at high densities in the cities
Myth 9: Green Belt policy leads to more land being used for golf courses than new housing
Myth 10: Green Belt stops any kind of development or beneficial land management at all so land is abandoned and neglected
Original source:
https://www.cpre.org.uk/what-we-do/housing-and-planning/green-belts
https://www.cpre.org.uk/what-we-do/housing-and-planning/green-belts/in-depth