As with Moore's Law for decades, there have been many similar predictions in the past, and they fell by the wayside as technology, output, and productivity improved. At some point, Moore's law gave way to more gradual increases, and the same may happen here, but we have no idea how or when.
- We might be sitting at a 500M population after the [climate / pandemic / AI / nuclear / system collapse / etc] apocalypse.
- We might be sitting on a terraformed Mars (or in bubbles under the ocean)
- We might be sitting in glass domes in the middle of an increasingly climate-hostile Earth
... and so on. We're very bad at predicting the future; it's hard to pick from thousands of (individually highly unlikely) possibilities.
Admittedly this isn't true of all possible scenarios. And in some, longevity would be really helpful.