Right. The solution is for those countries to develop, not depopulate. Bangladesh with half the population just means half as many people would be living at the same level of poverty. Nature is brutal, and humans in a state of nature are equally brutal. Nothing is free for the taking. It's not like resources are present for free, and halving the population would double the amount of resources per remaining person. There are few accessible resources. The production of useful resources and the maintenance of the infrastructure are massive undertakings by tons of people. Having fewer people also means having fewer resources. Fewer scientists and engineers to come up with new ideas, fewer workers to make them happen, fewer educators to pass them on to the next generation, etc. And the relationship is not linear. The maintenance of a resource has a minimum number of people required. You can scale down the number of people in a copper mine at the expense of having less copper extracted, but only to a degree. You still need a minimum number to keep the operation going. So a smaller population means a larger percentage dedicated to keeping things operating, and fewer people available for other tasks. So having half as many people doesn't mean half as many resources. It's a lot less than that. I honestly can't think of a major advantage to having fewer people, except for pollution. But then again, medical outcomes would be far worse due to diminishing talent pool and resources, so it's doubtful the health outcomes for even that one aspect are positive.
And that's ignoring the fact that the immediate consequences would be the utter collapse of human civilization if the rapture happened suddenly. I am assuming that the remaining humans will eventually rebuild something more suitable to their circumstances. But it's a long hard road to a *****er world.
