As far as life expectancy, if you do three things to the data:
1. Normalize it to account for war and crime-related deaths, so you only get data that shows improvements to medical technology,
2. Look at worldwide life expectancy, not just US, and
3. Remove time people are kept artificially alive in hospitals or in inpatient care without the ability to live on their own...
you find the numbers are essentially flat, with very tiny increases that are barely statistically significant.
(I quickly looked for the papers I used to calculate this for lifepath.me, but I can't find them right now. I'll post them all to that site when it launches, though.)
---
Interesting about airfare prices dropping. I didn't know it was by that much.
Growing up in the 1970s and reading lots of sci-fi, I expected that by my current age, I would be on an interstellar colony ship - or at least living on one of Jupiter's moons. I also thought the human race was sure to give up on traditional religious taboos and stop wasting lives and resources on war.
None of that happened, but as a consolation prize, modern smartphones and the internet are still pretty amazing and the social changes they are bringing about have obviously only just gotten started.
"But human life expectancy hasn't changed at all, really..." Since 1970 US life expectancy at birth has increased about 5-7 years: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5414a6.htm
"travel is still expensive (though cheaper, of course, but not by much)" Since 1970, roundtrip airfare between NYC and London has dropped, on average, from $2600 to $600: http://people.hofstra.edu/geotrans/eng/ch3en/conc3en/airfare...
There's still a lot of room for improvement, but since 1970 a lot has improved.