also, i really dont get the point of jon being the supposed "rightful heir to the throne"
a) as a recruit and former member of the nights watch, he renounced all les and birthrights. so even if he was the heir, he renounced it by taking the black. end of story
b) targaryens were booted out of the throne. they can kick and scream all they want, but the seven kingdoms all recognized the legitimacy of the baratheon throne. they recognized that legitimacy full well knowing that viserys targaryen was alive... and he would have been the "rightful heir" as the direct descendant of the previous king. its clear that the "targaryen birthright" no longer means . the seven kingdoms dont recognize them as legitimate rulers any more.
c) jon has made it clear he doesnt want any of this. he didnt want to be king in the north. he certainly doesnt want to be king of the seven kingdoms. he already believes enough in daenerys to the point where he wouldn't actually stake a claim for it.
considering C, the only way this has an impact is as follows:
1) daenerys learns of jon's position, and feeling threatened, turns against him leading to some drama in that direction
2) daenerys dies, and jon is able to stand in her place as all he followers: unsullied, the dragons, tyrells, greyjoys acknowledge that jon is as good as daenerys was and has the same claim of legitimacy she ever did