This is such bullshit and I have not a single good thing to say about you for pushing it on us. Not everyone in a famine situation in one year is going to be in a famine situation in the next year. Disasters happen but we still rebuild and help people get through the tough times, because those don't last forever. Situations are fluid, not fixed in place for all time.
If you actually look at what the UN itself is listing as causes for the famine, you will see they are not temporary, at least not with one year timescales: local wars and violence, corrupt governments, man-made environmental changes like deforestation and of course the big, overreaching one: climate change. All of which will quite likely not be solved by one-year band-aids.
"Not everyone" is too wishy-washy - how many do you expect to save in a permanent way with that sum? Is it 1%, 10%, 50%, 90%?
Saving someone's life doesn't mean that same life is going to just give out again the moment you walk away. That's why we have paramedics and doctors and social safety nets. Your mindset is exactly the same as those who want to cut food stamps because they think it means whoever accepts them has to live on the government dole forever.
I get that you can't muster up enough giving-a-shit to think about these things and realize you're wrong but it'd be great if you could accept that maybe it's just better to not post them.
I understand that is
easy to pretend that giving some money now is somehow solving things, but it isn't - it just the simple minded "thinking" that led to the current situation. You either commit to giving that kind of money every year for timescales that probably reach at the very least a couple of decades, if not longer (and hope along the way that mere survival will somehow change societies into becoming eventually self-sustaining ones), or you "invest" that money in more targeted programs, that actually help people grown their own food in a sustainable way, and actually "end world hunger".
I suspect that Musk would be more receptive to spending that kind of money on a plan that implements the latter.