Vegans literally are suggesting solutions to the growing population because in almost every situation, it is much more efficient by land and water use for people to eat plant-based rather than meat. It's only a "first world hill to die on" if you think poor people can't eat plants. Sorry but I don't think this is a very accurate take...

A not insignificant line of reasoning (though probably less important to people in power than the profit incentive) was also to keep the secrets of making the vaccine from bring revealed to other countries, which would apparently erode the USA's pharmaceutical research advantage. An interesting article about this from the former director of NIST is here but I don't necessarily agree with the reasoning.