The present model in fact gets messages from where
they are to where they need to go.
the present model in fact loses a fair number of messages. in my
experience, email is less reliable than snail mail.
My experience is that lost messages can usually be narrowed down to
anti-spam measures gone wrong, or buggy software.
that, and misconfigured software.
The second won't go away, and the first needs to be solved anyway.
we can make better anti-spam measures which will hopefully replace the
worst of the bad ones
we can design protocols that make it easier to configure software
we can make software that detects common configuration errors
we may be able to reduce the number of hops that email takes, and thus,
the number of opportunities for failures.