It’s actually funny you say that it seemed like a sci-fi fantasy thing. Mainly because people have tried to develop mainstream low bore pistols for a long time.

The idea is that the more inline the barrel is to the center of the hand the less recoil impacts accuracy.

Recoil only pulls the barrel up because the barrel is above the centerline of the hand creating a lever that pulls the hand up.

An inline barrel would push all that recoil straight back into the hand causing minimal rising with repeated firing.