I used to be a great airplane traveller. It wouldn't bother me like most people. As a former consultant I would fly all the time to various parts of the country and I was always one of the most relaxed and easy going passengers.
I'm still pretty easy going about the whole thing, I don't let things get to me very easily, but I've gone from tolerating one of the most painful experiences that any ordinary person might regularly do to getting pretty frustrated by the whole thing.
One of the reasons things have gone downhill from just a few years ago is that planes are much more crowded than they used to be. It used to be that I very rarely sat next to somebody on a plane. Not only would the middle seat almost always be empty, very often times the entire row would be. When you don't have to sit next to someone and you have a little more space, things are a lot more tolerable.
But now, airlines are starting to make sure their flights are full. This is partially due to just better planning on their part, but also due to less and less competition in the space. You see, airlines were money losers. They have been for a while. While this was bad for them, it was great for consumers. Competition forced them to offer a great many flights on a great many routes. But this killed off a lot of the regional and even major carriers. With less competition the surviving airlines aren't offering as many flights meaning the ones that still exist are more crowded.
Oh well. I hope one day, when the airlines become profitable again this will encourage more people to enter the space and once again give us the empty seats and frequent flights that marked the high point of travel for the consumers.