Earlier quoted context omitted.
There is 8 billion people in the world, with the number increasing still. You will always have to choose whom you feel responsibility towards, because all 8 billion are beyond anyone's capability.
I don't know about you but my answer is "the ones standing next to me that I have the means and ability to help sustainably."
Same applies to entire countries; their capabilities and societal will are greater than an individual's, but still limited.
Declarations of very broad commitments towards the rest of humanity may sound noble, but wise(r) people should stay away from them.