The biggest mistake made by almost everyone who claims that curing every disease within a decade, or accomplishing other insanely difficult things like reversing aging in such a short time, is impossible, is assuming that progress over the next 10 years will look something like the past 20 years, perhaps just a little faster. Yet, it will be radically different: the next decade will bring more technological progress than the entire past century. Just think of all the progress we had since 1900 to today happening in the next 10 years or so.
That means many things people assume are still 100 or 200 years away could become possible within the next 10–15 years. By 2050, we will likely see more scientific and technological advancement than humanity experienced during the previous 5,000 years of civilization combined!
This is the essence of the technological singularity: progress stops feeling linear and becomes so rapid, compounding, and transformative that the future becomes extraordinarily difficult to extrapolate from the past. And that is precisely why the concept is so difficult for people to comprehend, or accept, and also why some of us have such a conviction to keep claiming the impossible!