In the IPCC reports, Carbon Capture +Storage is a fairly significant variable.

https://www.ipcc.ch/site/assets/uploads/2018/03/srccs_summaryforpolicymakers-1.pdf

Under heading #19

19. In most scenarios for stabilization of atmospheric greenhouse gas concentrations between 450 and 750 ppmv CO2 and in a least-cost portfolio of mitigation options, the economic potential23 of CCS would amount to 220– 2,200 GtCO2 (60–600 GtC) cumulatively, which would mean that CCS contributes 15–55% to the cumulative mitigation effort worldwide until 2100, averaged over a range of baseline scenarios.

15% at the low end and 55% at the high end. And we haven't developed this technology or begun to scale it yet.

I think it's almost like Ponzi scheme accounting where your books balance as long as you get new investment in the future. We are planning on overshooting the carbon in the atmosphere and then doing negative emissions at some point later in the century.