[KoftaBob]

Air transportation only makes up 10% of emissions caused by the transportation industry, and that industry as a whole makes up 26% of total global emissions. In other words, air transportation makes up 2.6% of global emissions, which is not even remotely close to being a "major contributor to CO2 emissions".

As for your last sentence, if we can find ways to travel the world faster, why the hell not? Once we start having this attitude of "good enough", we stagnate as a society.

The biggest sources of pollution are passenger cars, energy production, and agriculture. Rather than stagnate our aviation technology in order to tackle something that makes up 2.6% of pollution, let's make those other industries green.

[jabl]

As another poster pointed out, the climate forcing due to high altitude emissions is about a factor of 2.6 worse than the CO2 alone. So 2.6 becomes about 6.8%, and rising fast. And to make it even worse, we basically know how to decarbonize other forms of transportation and electricity production, heating, some major industrial processes etc., meaning that when those solutions start rolling out at scale, air travel will rise even faster as the proportion of the total.

By all means, let's continue developing aerospace technology, but I think it's a fantasy that we'd be able to have anywhere close to the same volume of flights as today in a decarbonized world.