User blog comment:Thetwindler/Dropped/Discarded Ideas throughout the seasons/@comment-2605:A000:122A:408A:91E8:8778:19BB:9B0B-20191214224113/@comment-108.36.76.116-20191217191613

I think all the stuff in season 15 are Bobbie's cosmic consequenses.

Sam made a choice to remove the mark of Cain.

Dean chose to kill Death.

Still, if Castiel had let one of them die, maybe another path would have resulted.