I would like to take a moment to address the idea that letting weak hives die is "inhumane."
Firstly, everything dies. We can all agree on that. But it's an important point that gets lost here. So all bees are going to die, the question is when and how.
Secondly, bees are insects. Insects don't have a long lifespan. Honeybees live about six weeks. Their life is short and full of hard work. Unlike humans which are adapted to live many years and with high intelligence, bees live short lives with a limited number of learned behaviors.
Third, they don't feel the same way we do, they have different nervous systems, different lifecycles, and they're cold blooded to boot.
Fourth, letting a hive die is not at all like letting child or a pet die. A hive is a collective organism. And as I said above, it is cold blooded. A hive that dies in winter simply slowly ceases to function. A hive that dies in summer, the workers will find new hives to join. But eventually they're going to die anyway.
Fifth, in fact, I'd say it's probably more inhumane to requeen a hive, to physically go in and kill a long living insect with your own hand.
Sixth, bees short reproductive cycle allows them to adapt much more rapidly than people. And they have to because they don't have the brain power to learn things and they don't have a long life in which to learn them. They are entirely unlike mammals, most especially humans.
It is not inhumane for a creature to die in a natural way. It is not inhumane for a gazelle to be brutally killed and eaten by a cheetah. It is the way things are. It is how our planet works. Inhumanity comes from how we treat people and other animals, causing them unnecessary pain in the process of controlling or killing them. It is not inhumane to allow a colony of insects to cease to exist under their own power because they don't have the genetic tools to deal with their diseases. It is nature. It is not only the way things are, but the way things ought to be. Treatment-free Beekeeping seeks to return that natural balance to the bees and not interfere in dealing with things that they should deal with on their own. And the feral bees from which we glean our wonderful survivor bees are already doing that.