Sturmvogel I hear where you are coming from, its a very valid point you are making. I think when you compare what the aviation industry has done in engine developement when compared to the old combustion engine (automotive) industry it aint doing so badly.
This is not to say that more cannot be done. As much as we all hate the noise taxes etc placed on our industry it certainly does motivate big industry to build better engines to sell to airlines so as they can try and stay one step ahead of the regulators.
It is a bit of a vicious circle but it is certainly helping the industry make large improvements in engine and aircraft design and the upside for drivers is that it is the only way accountants can be enticed into buying new airplanes for us to fly . That is they can see a 'buck ' in the efficiencies the new types give.