[1]https://www.npr.org/2024/01/08/1223517098/door-plug-boeing-7...
Flying is also a pretty mature technology by now. We've done it for more than 100 years and the physics is well understood. Massive leaps in capabilities are unlikely, much like no one will develop a pistol with a 2 mile range or a coffee machine that produces an espresso in a blink of an eye.
What you can do is add more sensors and software, but the increasing complexity may not be worth it.
There are massive improvements still possible in the engine. Like the currently in design RISE engine. And other engines as well. And if you combined the technology you can get even further. We are not close to the end on any of this. See: https://www.youtube.com/watch?v=XkHKet7rp4o
There are various aero-dynamic concepts that have not yet been fully or even partially explored. Trust brace wings, blended wings or my personal favorite, Prantdl Wing. A Prantdl wing might allow you to remove the whole tail, another huge potential boost. You can even combine all these concepts potentially.
I would guess we can get 40% more efficiency just based on those things.
> That is more of an argument for stricter requirements around automobiles and that entire industry than anything else.
I agree that cars should, and could, be safer. But my argument was about the reaction people have to accidents. In cars we have several orders of magnitude more deaths and we don't bat an eye at that but in aviation we have a scary incident and it is wall to wall coverage.