I'm a Christian, so I know the point you're making. But I'm also a technologist, so I know "ancient peoples" also believed this planet was flat and that everything revolved around it.
According to almost every culture since the dawn of time. Almost every culture had myths about hades or the underworld. If you will notice in Roman myths people could travel into and out of the underworld without dying. Its obviously an ancient peoples way of telling stories about a certain kind of energy. The stories were flowered up and embellished to try to tell serious observations about life to children.
Are we still stuck in "dawn of time" thinking?
We can demonstrate conclusively that planet is NOT flat and that the universe does NOT revolve around it. Yet as far as an afterlife goes, with very minor exceptions, we can demonstrate - NOTHING.
That was the Roman Catholic church which was quite repressive of all scientific thought, other ancient cultures didnt share that belief. The Ancient Greeks and Romans in several texts made observations concluding the earth was round.
You're missing the point about Hades also, in Roman myth it was more like a plane of existence than a Christian style afterlife since living people could go there.