Jon Snow has to be the guy who rules. Even though he knelt down to Dany, according to Brans vision he is the one true ruler, and doesn't look like the guy who will be the hand to the queen. What are the odds on him ?
But do you think GRRM is going to give such a poetic ending to a show which is infamously known for killing main characters? Past two seasons we are seeing that the iron throne is not important, so it might happen that neither Jon nor Dany end on the throne but some 3rd person, could be tyrion he is a good political ruler better than Jon or Dany IMO.