Atheists by and large don't outright reject the possibility of the unknown. They just don't hang their whole lives on it and make up stories to make it less unnerving to contemplate. The fact is we can't know everything, and our collective knowledge as a species probably barely scratches the surface of reality. But we can rule certain specific use cases out on a logical basis.

Almost anything is possible. Likely? Fuck no. But possible.

No worries about the downvoting. There's no karma display :P

Tbf I don't see anything weird in being an atheist and believing in souls in the philosophical sense, as a part of consciousness in humans, animals and perhaps advanced AI in the future (but it's a whole different topic) that lets us experience reality rather than being glorified chunks of matter which just exist.

Maybe there's a better term than soul for this, but it has nothing to do with the concept of afterlife.