This makes the assumption that life is simply about progressing the human species. Progression to what though? One should aim to lead a happy life, of which making things better for the next generation is a byproduct.
Indeed. That is the assumption I made. Personally, for me life without progress is a meaningless one. But I can imagine the opposite as well. Once you have gotten all you need you try your best to preserve it as long as you can, anything new or different is a default no, because, why change something that is not broken? That is depressing, again from my perspective.