With CFCs it helped that a single company manufactured 25% of the global supply (according to Wikipedia anyway: https://en.wikipedia.org/wiki/DuPont#Chlorofluor

With CFCs it helped that a single company manufactured 25% of the global supply (according to Wikipedia anyway: https://en.wikipedia.org/wiki/DuPont#Chlorofluorocarbons https://en.wikipedia.org/wiki/DuPont#Chlorofluorocarbons) and when presented with evidence that they were harming the environment, led efforts to find alternatives. CFCs were a great victory, and encouraging when it comes to battling CO2 emissions, but also much easier to curtail both politically and technologically.