We won't stop pumping CO2 into the atmosphere (Germany, India and China actually increased coal burning in 2026, in all 3 cases despite all the good news about solar installations). Also we can't prevent fossil fuel producers from digging up fossil fuels.

And, because of entropy, reducing CO2 already in the atmosphere is a non-starter. For one thing, one can reasonably assume that would at minimum require doubling human energy output (because unmixing costs a lot more energy than mixing)

I mean if you put the belief behind the whole CO2 reduction in words, it's like this: if we slightly reduce CO2 output (not stop, reduce by single digit percent), we won't have to adapt. And if you put it like that it becomes easy to see: "no way in hell that's going to be true".

So there's not much of a choice: geoengineering it is. Next question: which method?

> We stopped high sulfur when we realized it was causing acid rain

Coal AFAIK a bigger source of acid rains and world has not stopped using coal.