When are we going to get a good young heavyweight like, Ali, Foreman or Tyson that can go unbeaten?

When are we going to get a good young heavyweight coming along like Ali, Foreman or Tyson who can go 50-0-0 for example? And what will boxers be like in 100 hundred years from now and when will the second coming of Ali occur at heavyweight? It is like Halley's Comet as we see it every 70 years or something most famously at the Norman Conquest during The Battle of Hastings in 1066 when William I (The Conqueror) defeated King Harold II. So it could be the same time frame (every 70 years) before seeing another golden generation of heavyweights.