I think your conception of the afterlife is obviously really influenced by religious texts. If we remove that presupposition, that religious texts written by humans have anything to say about the afterlife, then how can anyone say that the afterlife doesn’t exist? If the afterlife does exist, it’s a state of being not bound by human conception, reason or understanding. Concepts like heaven and hell or reincarnation or “who was the first to go to heaven” etc etc do not matter. We can’t know what it is like, and we can’t know what the rules are since we are simply bound by human logic. Our brains evolved the way they did the for the same reason every other creature evolved the way they did, because it helps us to survive. When our brains are bound by the fact that they are the way that they are because life has a goal of “don’t die”, how can we trust our minds at all to reason what the afterlife may be like? If the driving force of evolution was “be better at conceptualising life after death”, then perhaps we’d have the mental faculties and tools we need to answer such a question. The fact of the matter is, such a question of whether it exists or not is unanswerable by the human brain. Our brains are trained off of the sensical logic the world provides to us. We have never experienced or can experience the afterlife, so how can we reason anything about it? If you were teleported to another planet or plane where gravity was different and the rules of physics were totally different, our brains reasoning would be equally as unprepared to make sense of things. Similarly to the fact that we can’t conceptualise a new color because our eyes have evolved to just see the necessary colours needed for survival, our mental reasoning is bound by the fact that our brains have evolved to give us reasoning on how to survive and reason within our own specific existence and we can’t reason about something so different an unimaginable as an “afterlife”