You seem to assume that you can only have a meaning to life if there is an afterlife.
Most people judge themselves against a narrative that matters to them. Most people do not want to cast themselves as a villain in their story.
You may ask "but what does it matter if we are all dirt". It matters to them, even if there is no godlike perspective above it all. To be honest, I'm not actually sure why having an afterlife or some super-being would create any more explicit meaning for an individual life.
Most people judge themselves against a narrative that matters to them. Most people do not want to cast themselves as a villain in their story.
You may ask "but what does it matter if we are all dirt". It matters to them, even if there is no godlike perspective above it all. To be honest, I'm not actually sure why having an afterlife or some super-being would create any more explicit meaning for an individual life.