Technology. That's the cause of what's happening throughout the years. Compare F1 these days with the ones 10-20-30 years ago, F1 (and cars generally) used to look less complex. Technology have moved us to a point in which we can engineer and develop ideas and construction who were too complex, expensive to realize 10-20 years ago. If consumers can 3D print something nowadays, imagine the advanced capabilities of F1 teams. I admit cars in the past look less complex and smoother than F1 today. The attention to detail these days are incredible. Gurneys, flaps, edges, leadings, holes, etc. you name it. These extra's have become far more detailed year after year and that's not going to change if you want to win.
2013:
2014:
The technology in F1 is one of the things that makes the sport very attractive to watch. Turbocharged V6's with ERS sounded impossible, yet they still have shown us that it can be done. Cars have gone on a diet throughout the years. Packaging of a F1 car looks so much more neat and compact.
2005:
2014:
People might complain how boring the cars sound or ugly they look. For me it's part of F1, the evolution race. I only hate when there's no competition. It means, other teams haven't done their job properly. I do however admire the single team that keeps dominating, because it means they have really done something special by setting the pace, which only can be beaten by themselves during the season. This season we saw that more than often, luckily we have a team that let's their drivers race to an extent, unlike some teams who only serve one of their drivers.
F1 is maybe a masterpiece for technology, but F1 isn't faultless. To me the business itself remains troublesome, because it looks outdated and needs to be revised.