But this depends on global willingness to do so by choosing (more expensive) sustainable products and voting for politicians who want to enforce/encourage carbon reductions
1. Is there any reason at all to believe that billions of people will change their minds and make both of them happen in a century or less?
The New Soviet Man was an experiment only 70 years in the making, and it was in no way a successful one.
2. Let's suppose that actually happens. Let's suppose we get to 50% of current emissions in... 50 years.
We currently increase CO2 concentrations by 2.5 ppm/year. This would put us at over 500 PPM in my expected lifetime... In one of the more optimistic interpretations of your predictions.
For bonus points, even if we hit 50% reduction in 50 years, that would way overachieve what the Paris Accord set out. We are currently not on track to hit any of the targets in the Paris Accord.
But this depends on global willingness to do so by choosing (more expensive) sustainable products and voting for politicians who want to enforce/encourage carbon reductions