Conservation of mass and conservation of energy gives a very easy planetary scale answer to this question.
From an energy standpoint, what it costs to bottle up the CO2 is equal to the following:
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Take all the energy (heat + work) that was chemically embodied in all the historical fossil fuels. We need to run all those chemical reactions that released energy again, but this time backwards.
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We need to also add the energy it would take to run the thermodynamic change backwards, because the original energy was in concentrated high density form, and now the carbon has dispersed to a low coherence state where it's stuck in air, ice, water and vegetation all over the place. It all has to come back out which involves major material movements and filtering / transformation
In conclusion, this is more expensive than all the money and energy and materials in the entire human history put together.
Unless....
Do you know of any magic?
To be clear on what's required, we would need something like a free infinite energy source that doesn't pollute at all. It also would have to be rapidly scalable within a decade or so. At that point we could have a giant vacuum cleaner sucking all the CO2 out of the atmosphere. We need to discover this new technology yesterday and it needs to clean the whole planet in about 20 years.
At this point in the story, we are adding about 1% to the CO2 pollution per year. Given the vast scale of the solution we will be coming up with, do you think this extra 1% or 25% will be somehow pivotal?
To me, this is like having pancreatic cancer that's untreatable by medicine and deciding if you are going to quit smoking or not. Yeah, smoking doesn't make it better, but in the face of the only cure being basically a miracle, is it actually meaningful to ask this question?
Like, a miracle that can cure an unfixable problem is so huge that do a few extra cigarettes hang in the balance?
I mean...of course you're right. Slowing down CO2 pollution is very very important. In 1950.
(We do not have 50 years. Lol.)