Just because something is industry standard, it doesn't mean perfect.

Just because something is widely supported, it doesn't mean that's the best.
Just because something is used by most people, it doesn't mean there is no better solution.
Email is far from the best identification method.
We just rely on it because it's widely used and the tech is decades old.
But in most cases, centralised, not secure, slow and unreliable.
Soon email won't be a reliable identification method to identify yourself as human.