Speed of airplane

Think of semiconductor stuffs like computers, cellphones or TVs. There have been huge improvements last few decades. computers get much faster, cellphones get smaller and powerful and TVs get thinner and provide sharper and cleaner images than TVs 10 years ago. Mechnical stuffs also get better than before like cars, robotics or appliances. If I think anything in my life, these stuffs are better than before. However, one thing that is not improving much is the speed of airplane. I am talking about regular passenger airplane. Their cruising speed is about 900km/hr or 600mile/hr. This speed is almost identical to the speed 30 years ago. With that speed it takes me 12-13 hours to go to Korea. Way too long. I hope the speed of airplane should improve like other stuff I mentioned above. If it flies 2000km/h(doubling speed), it would take me 6 hours:)