The concept of bottlenecks preventing the singularity are a fair point, but I don't believe many of the arguments that are made here. Using humanity as the basis of comparison is not sufficient, since human life expectancy and other requirements for survival are not a factor in artificial superintelligence.
Humans work for perhaps 60 years at improving themselves and their understanding of the world, but must sleep, must eat, must go and stand in line at the DMV, etc. Having a system that can work 24/7 on improving itself for 20 years will match a human lifetime. After a lifetime, humans start over from scratch, with perhaps some learning that can be passed down between generations. AGI can simply clone itself, and begin from exactly where it left off.