Your explanation is just as good as the Fermi paradox. In Futurama, the Omicronians know about the Earth from old TV show signals, that's been constantly sent from Earth by then. Would any alien civilization have the patience to constantly send hello world for a millenia or maybe hundred thousand years.

Both assume that there _is_ some other life, but that it's hard to reach. We don't know if there is anything else.

Earth could be completely unique in the existence, even with all the endless multiuniverses. Mathematical propabilities are not proof that there _must be_ life somewhere else. The answer could just as well be '0'. Only life that was, is and will ever be. When we are eventually gone, that's it. No more life.

edit: sorry about the negativity in my reply; just pondering out loud :D