"they" for some value of they knew of the properties of sulphur compounds in advance. The minor shade advantages didn't count much against the billions of tonn

"they" for some value of they knew of the properties of sulphur compounds in advance. The minor shade advantages didn't count much against the billions of tonnes of additional insulating gases added each and every year, and the decision was made to remove sulphur compounds because of the downsides of using them - acid rain and other consequences. That said there are private groups that collecting money as credits and putting sulphur back into the atmosphere as we type .. they're here on HN and may or may not be doing a good thing.