A really great screenplay is undeniable. Is this true?

Since the topic comes up a lot I wanted to start a conversation.

Do you believe that if a screenplay is truly good, that no matter what your connections are or if you happen to get very lucky, it will eventually see the light of day? I understand if nobody in the world reads it then nobody will ever see it. But say you host it on a site and have no connections, what are the chances that it just being really good will propel it into the next stages? Is there still an element of luck?

Are there brilliant screenplays out there that nobody has ever read and will never get production? How many ( what percentage)?