Wait, so according to your theory, Barry's actual Joe and Iris drowned in a tsunami? That's awful. How would Barry react if he ever figures out how time travel works? Do you think he will?
For Our Barry’s sanity, I hope he doesn’t find out on his own. I headcanon that some older Barry – usually either the 35-year-old 2024 Future Barry or the 67-year-old 2046 Barry – tells him how time travel *actually* works. It boils down to “Heyyyy, all of those universes? Happen/are real/still there. Including the ones where Cisco died, and where the tsunami happened, and where Vandal Savage won, etc.”
That’s the thing with time travel: you never really undo anything. You just walk away from it. Which is why it is absolutely essential to prevent disasters in the first place rather than trying to course correct after the fact. If you course correct, you don’t solve the problem; you abandon it. If you prevent, you avert the disaster. You save people if you stop it; but just because you aren’t there to see it doesn’t mean the disaster doesn’t happen.
If Our Barry finds out on his own, it’d be a devastating realization. How could he have left so many people to die? How could he have just … walked away, pretended it was all fine and well?
I’ve written a cluster of fics about it (bolded the most important; focus: Home, Mutability, Divergence, Survive, Terra Incognita, and Dear Future Me; prominent factor: Aftermath, Realities, Erudio, Uncertainty, Echo, The Weight of Everything), but I’ve yet to write a fic that addresses this issue head-on, because truthfully it is a *dark* premise. It’s the reason why Eobard doesn’t flinch at killing Cisco, and the reason why Zoom doesn’t care about time remnants. It’s the reason why Barry is dangerously “like Zoom,” and like Eobard, in his obsession with changing his whole world at the expense of others. He doesn’t know just how profoundly he is altering the shape of the multiverse.
He’s gotta stop tipping dominos before he kills more time remnants. He already has Barry-5′s, Barry-6′s, Barry-7′s, and Barry-8′s blood on his hands. (Respectively: Out of Time, Legends of Yesterday, Magnetar in The Race of His Life, Behind-the-Door in The Race of His Life reboot of the Fast Enough event). That doesn’t even include the Flashpoint reboot of The Race of His Life, which would have destroyed the Intruder Barry. It also ignores the Flash Back Barry-4 who died when Barry-2 wiped Barry-8 and all of their collective descendants from existence. Barry-2 – Our Barry – has done some real damage.
It’s a complicated conversation. Given more time, I would truly love to explain. As it stands, I’ll leave you with more questions than answers for now.