I think a lot of these issues also has to do with simple population growth. The area I live was very unpopulated back in the mid-80's when I started riding, but now all roads seem to be packed. There has been a 30% population increase between 2000 and today.
However, as bad as it is here I can imagine larger cities. In the D.C. area, where my family is from, has grown even more. I'll never complain about my local traffic, because I know just how bad it can get from my occasional visits back home in Maryland.
EDIT: Yes, the issue of today's phones don't help, not just because people have phones, but because they are so capable that just saps people's attention.
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