User blog comment:LoneGunMenWander/Should the Elder Scrolls Six protagonist still be the Last Dragonborn?/@comment-26213507-20160526200413/@comment-1600847-20160527120138

First Bethesda would have to tie up the story of the Eternal Champion, Hero of Daggerfall, Neverarine, and Hero of Kvatch, which were left unanswered at the end of their respective games :P

I think Bethesda leaves their fates ambiguous on purpose.