If you are talking about “natural” humans, Gunther, what you say is already largely true, and hooray for that. Today’s humans are much more protected against nature’s fickle fist than in the past. Will we build the end of humanity, though? Is it not equally likely that we will continue to enhance, rather than replace the natural human condition? As the genetic tumblers fall into place, there are boundless possibilities for our direct – if perhaps no longer traditionally human – descendants, and it seems likely that partially, but not totally trans-humans will take our place, who will integrate idealized genetics as well as trans-human upgrades.
I don’t mean to misrepresent myself as a studied expert, but it seems that the end-game outlined below is a possible extreme outcome, but not hard fate.