Or maybe save a lot more lives than 10,000 over time by doing things that keeps the species aspirational, helping avoid protracted regression and short-term thinking.

For another example, building out space infrastructure.

The notion that the other things we do, with creating and building, often don't pay off in a radically superior way than directly saving a life, is ridiculous.

How many lives could we have directly saved instead of doing the space race? How about: instead of a space race, the US and USSR focus more on regressive behavior, war, and nuke the shit out of eachother, killing hundreds of millions of people.

How many lives will the transistor have saved, improved, or made possible over a century: should that investment have gone into saving 10,000 or 100,000 lives back then instead?

Your setup is a false choice.

I do actually find the project fairly neat, and I'm not saying it shouldn't be done. Just wanted to start a discussion about a different aspect of this and see people's arguments because opportunity cost definitely exists, and the allocation of our limited resources is a difficult and interesting problem.

Also, I would contest that some of those charities are arguably long-term thinking as well.