In my opinion, he didn't owe the world anything - yet he's donating quiet a bit (clean water, anti-malaria etc.) - Sure he's got luxuries that most of us would probably dream about - yatches, jets etc., but he's also done net positive to the world and that's great.
Usually people who share my view generally counter with "so what have you done?" and imo that's a wrong way to think about it - everyone's level of contribution will be different.
If I were in his position, I too would have spent on luxuries (maybe more so than him) but the end goal is never lost - he's still helping people all over the world.
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My political view on the topic: in a way, your comment reminds me of the previous election - moral policing of "oh, Trump's against X" and that's terrible and if you support him for Y, you are still a terrible person because he supports X lead to the result - people who supported him for Y were unable to ever get Y discussed and every time they did, X was always brought up, dismissing Y - so they never bothered discussing/learning etc and instead did the only thing in their power - look after their self interest of Y.