I can’t believe this is even being disputed.
Have you missed the force choke discussion?
This beats the force choke debate by a mile.
I can absolutely believe there is a dispute because people come with different frames of reference for what they see.
In this case, Kylo is laying flat on his back defenseless and Rey in command standing over him. To me, that’s beaten.
We could imagine that Kylo might refuse to yield, Rey wouldn’t be quick to strike, and all kinds of gymnastics and force powers might ensue. That’s a reasonable thought, but that didn’t happen. By my criteria he didn’t need to surrender or be unconscious/dead to have been beaten. The fight ended when the planet split and at that point Kylo was beaten. That’s no different if Rey simply ran away at that point, that wouldn’t mean it was a draw or that she lost.
Just thought I’d add thoughts beyond: I can’t believe you think that!