our dovakiin cant light the dragonfires, the septims did not have souls of dragons they had the blood of dragons (which is really just tiber's blood, a relation of somekind with tiber would do)
Nobody can light the dragonfires, they no longer exist... However they have been lit dozens of times, like during Alessia or Reman their days by people that were not related to Tiber Septim. Tiber his blood has nothing to do with the dragonfires.
svcks that we're told what to believe. Like there's no room for questioning the nature of gods. Everything written about them is apparently true, and there's no alternatives.
Really then please answer the following questions:
Is Tiber Septim Talos, or are Tiber Setpim Zurin Articus and Wulfharth Talos?
Did Lorkhan trick the Aedra into creating the world, or did they do so willingly?
Is Akatosh an aspect of Auri-el or is he Auri-El?
Is Mehrunes Dagon, Magnus? And does he as such actually have a claim to Tamriel?
How did Arkay come to be?
What side are the Eight/Nine on?
Is CHIM possible for all, does Shor want that?
And these are the first few questions I could come up. TES has almost nothing set in stone.