The question is not how much oil we have left but how much of it we may still burn.
If we keep drilling for and burning fossile oil at the same rate right now it will very soon let the effects of it, specifically global warming exponentionally worsen. It is true that we might have decades of fossile fuels left over, but we can’t ever burn that all if we would want to keep this planet an inhabitable home for many further generations.
The plane of the future in my subjective opinion is a zero-emission, perhaps solar-powered or at least “green” energy loaded aircraft with about the capacity of a rather small long-haul airliner and the range of this new Boeing 797 concept.
By 2030 already, we will have about 1,000,000,000 more people living on earth than now and this leads me to being concerned more about the regular medium to short-haul travel than a couple transatlantic flights.
There will be a point when our usual short to medium-haul airliners like the 737 will not be capable of running the routes they fly anymore because of capacity issues. More and more people are living on earth and the percentage of people using air traffic as their mean of transport is increasing just as quick.
Airlines like Swiss, Austrian and British already use 777s and 767s for routes like Vienna - Frankfurt, Zurich - Vienna and London - Amsterdam. And that is only one of countless flights on these routes each day. If zero-emission aircraft don’t become a reality, running larger capacity, fuel efficient planes a couple less times a day rather than more low-capacity aircraft will over a long course perhaps be the better solution for our planet, air congestion, those affected by aircraft noise and so on and so forth. It may make us dispense with comfort in terms of frequency of flights and travel times, but I don’t think I have to elaborate that our earth is more valuable than arriving somewhere 1 hour earlier or later.