Hypothetically if we can somehow get to net zero emissions and have scalable carbon capture, I think it will have taken long enough that geoengineering like stratospheric aerosol injection will be necessary to alleviate the worst of the warming from the extra gigatons of greenhouse gasses we've already put into and will have added to the atmosphere to get to net zero in the first place. Without some kind of artificial cooling effect and something to stabilize rainfall patterns, some degree of industrial agriculture collapse and famine seem inevitable to me down the road.