Optimization for respectability is a good reason. If you don’t even try to convince anybody who thinks that nanotechnology is simply impossible, then you won’t make much impact outside singularitarian bubble.
Lalartu2
For this outcome, everything below has to be true:
Molecular nanotechnology is impossible.
Maintaining infrastructure using only robots is impossible / highly impractical.
It is not possible to genetically engineer a creature that is a vastly better maintenance worker than human.
Given that, 95% claim is very overconfident.
I disagree that “France in the Year 2000” predictions were wrong. If judged by function rather than aesthetics they are more than half accurate.
First, there were industrial nations which were autocracies and lacked significant middle class. For example, Russian Empire of early 19 century. So the argument “no industry without middle class” is simply wrong.
Second, this chain of logic relies on every alien species having such social group as nobility. This is utterly absurd. For heritable social status, it is necessary that upper classes have the same (or lower) number of (surviving) children as commoners, otherwise in a few generations everybody would be a nobleman. This only happened because humans are poorly adapted to civilized life. For civilizations that exist for millions of years, evolution would definitely fix this.
We technologically plateau because we reach technological limits. There aren’t many important technologies not invented yet, things like nanorobots, compact fusion reactors or Dyson spheres are impossible. Whether AI is developed or not is irrelevant. After a century or two of stagnation, civilization runs out of resources and declines to pre-industrial level. This is our future.
The FTL argument is just wrong, for two separate reasons:
Declared conditions allow an FTL drive that has sufficient range for interstellar but not intergalactic travel.
The whole “Earth is young” thing depends on assumption that red dwarfs can support complex life. There are good reasons to doubt that. And without red dwarfs, the argument falls apart completely, as for a yellow dwarf star the Sun is not early.