Yeah, I agree hinventon. I haven’t given it this much thought before, but it does make the most sense. It literally makes their duel on the Death Star wreckage another “duel of the fates”, because only one of them is going to make it out alive as Palpatine’s rightful heir. In my last draft, it’s clear both of them have seen that it is fate for only one of them to take the dark throne (Luke sees this vision of Ben in his mind from TLJ). That’s why playing the “duel of the fates” motif there now makes sense and isn’t just fan-service. Leia’s intervention allows both of them to walk away still on the light.