[schiffern]

Morality does play a part here, but what you took for "moralizing" is me pointing out how the framing of the question constrains the answer. Specifically this passage:

>>>The basic problem is this. There are a great deal of resources that can be brought to bear on solving problems in the world. There are lots of philanthropists in the world, with lots of money.

Yes, those things are true. There are also people over there, and their participation matters at least as much as (and I would argue much more than) that of the wealthy elite.

In the case of the "carbon-sucking gizmo", the cure is worse than the disease. Even Branson-level cash can't change thermodynamics and evolution.

The Virgin Challenge finalists are conspicuously absent in their energy and land use analyses. I expect they suffer from the same problems as previous CCS "solutions" — energetically they can't compete with simply shutting down a coal plant, and in land use they can't compete with reseeding farmland to forest. So when you understand why those simpler methods aren't done, you'll understand the finalist's actual scaling problem.

It all washes out in the lifecycle analysis. Anything else is feel-good.