Humans are the most amazing thing that has happened in this universe. David Barrow summed it up neatly in the title of his book: "The Universe that Discovered Itself". The idea that the human story should end and be replaced by a superhuman or nonhuman world is something that people are too willing to accept: even otherwise intelligent people.
The first point to make is that there is not a requirement for change to make way for progress. Humans are tool users. Humans with intellectual and communication tools provided by Information and Communication Technologies are not limited in what they can achieve (relative to computers or improved humans).
There is an idea in the populace that when computers pass a certain level of intelligence they will magically acquire motivation. This is not the case. Our motivation comes from our genes. Our genes have motivation but it is not the same as ours. In the simplest example: If I or my identical twin brother is going to drown, then my genes don't care which. Genes give us complex motivation in which the desire to live and the desire to reproduce are only the most trivial parts. But the fact that genes, even in the simplest bacteria or virus, display clear though unconscious motivation shows that motivation is unrelated to intelligence.
Sure we could give our little machines motivation. We might accidentally give them enough motivation to wipe us out. What we couldn't do is give them the sort of subtle motivation which genes supply that keep us striving to understand, to explore and to conquer the universe, while at the same time perpetuating ourselves and living fascinating lives that we turn into literature and other art. In fact I'm certain that any motivation that us junior gods could bestow on our creations would grind to a halt very soon after we became unable to guide it.
And losing the ability to lead is the great danger of this inhuman or partly human world. If people start living for ever then we will quickly lose the input of youth that keeps human society fresh. The replacement of humans with computers and robots in positions of any importance will lead even more quickly to the loss of humanity's spark.
If machines were given motivation that would make them independent of humans then that would be a terrible crime which would hold the seeds of our destruction. Any motivation less than that would be sufficiently weak as to be no motivation in the big scheme of things.
There is no choice to a human future. The hard bit is to understand what that means in a world where many people have ignorant plans to change humanity. Our present life has already acquired features which will drive evolution towards something which is not fully human.