I've looked into this area. I agree with the author that current sources of carbon offsets are poor and sketchy. However, that's not to say that people aren't working on more promising methods. Direct air capture and growing and sinking seaweed are two things that I think definitely pass the additionality aspect.

A big problem, I think, is that the market doesn't really differentiate between these, and that there are no strong regulatory pressures to buy "good" credits. We don't have a carbon tax in the US, and we don't have anything that pressures companies to say, if we want to buy offsets, that we only buy "good" offsets.

To people who say we need to move off fossil fuels - yes, but how do we do it? We can't just move our physical processes from A to B process.

It seems to me that imposing economic costs for every extra unit of carbon emitted, and only allowing high-quality offsets to subtract that, is the best incentive to move forward.