I am very skeptical of atmospheric carbon removal as a viable path to stopping global warming - especially given the extreme systemic risks of most of the ideas I heard, such as seeding the oceans with iron; but also the extreme difficulty of others, such as re-seeding enough forest area to actually matter.

So, my temptation is to say it's just a publicity stunt. But, I am prepared to praise it if it produces some viable solution, as unlikely as I believe it is.