I think one of the series charms is that, up to this point, Harry has had to depend on dues ex machina ways of surviving Voldemort...which is something that Harry is very aware of. I doubt that Harry will ever be as powerful as Voldemort, even at the end, but he has other forces working for him, like the love of his friends and family. Voldemort doesn't understand this, and that is really Harry's only edge, even though it is a powerful one.

Like most fantasy, Harry Potter works best when you don't overthink everything.

I blame the internet.