you realize that the 42 billion dollars isn't burnt in a furnace right? it was spent on research, labor, hardware. that money reaches new hands. it can be spent again.
what a nonsense comparison. anyway, you're showing a misunderstanding of the complexity of capital allocation.
So he should have donated 1 billion? why not 2? why not 5? why not 10? well hang on, 10 billion for greening some areas? That's not an optimal use of 10 billion. 8 of those should go to doctors without borders. wait hang on, have you seen the ukrainian refugee crisis? and you're putting 8 billion towards doctors without borders? they should get at least 3 of that. wow so you've donated 10 billion dollars but not a single dollar towards educating women in third world countries? etc ad nauseum.
I guess your take is probably that it's his responsibility to donate 100% of his wealth optimally across the world, and spend the rest of his life doing that. but i'm appealing to people with more sense when I say: don't underestimate how difficult it is to "correctly" spend a large amount of wealth.
can we not conflate facebook.com and twitter with big tech? big tech is driving many of the technological advancements that have brought a new era of economic prosperity and growth to the world. hundreds of thousands of high paying jobs, tools for small businesses, a wealth of high quality information at our fingertips, the likes of which was one generation ago unimaginable.