We didn't have the same arrangement as you have here with supply management, but what we did do was remove all our agricultural subsidies in the 1980s. We didn't provide any industry support under specific sectors. That enabled the farmers of New Zealand to move into the most productive and profitable areas of production.
Back then we were supplying a lot of wool around the world. Wool prices went down. The economy went down as a result, but deregulating the agricultural sector enabled the farmers to move into more profitable sectors like dairy production or wine production.