I'm not sure where you found this idea - I don't know any EAs claiming there is a single best optimum for the world. In fact, even with regards to charities, there are a lot of different areas prioritized by EA and choosing which one to prefer is a matter of individual preference.
The real world has optimums, and there's not a single best thing to do, but some charities are just obviously closer to being one of those optimums. Donating to an art museum is probably not one of the optimal things for the world, for example.
The real world has optimums, and there's not a single best thing to do, but some charities are just obviously closer to being one of those optimums. Donating to an art museum is probably not one of the optimal things for the world, for example.