I am completely against…

I am completely against opening up any part of the Greenbelt for development, whether it is for housing or for a highway. The Greenbelt is a vital area which stops sprawl, protects farmland, forests, wetlands, biodiversity, endangered species and the sources for our drinking water. It also is a carbon sink which helps to mitigate the effects of climate change; it also prevents disastrous flooding and landslides. In addition, allowing some development would incentivize further requests for Greenbelt land development to the point where no parts of the Greenbelt would be preserved. There is a vast supply of unused "greenfield" land already open for development within existing municipal settlement boundaries. Building affordable housing within these existing settlement boundaries and existing low-rise single detached neighbourhoods is the way to solve the housing crisis that we are in.
Add to the Greenbelt by all means; protect it in its entirety from development. Once it's gone it's gone and the damage will be irreversible. The future of other species and our ability to feed future generations is dependent upon our wise actions today.