It is very easy not to be seen, and that applies to everybody. I was almost in a collision (driving) when I didn't see a truck before starting to enter the road. Let's face it, a truck is pretty hard to miss, but I managed to do so as I turned my head to check in both directions.

Anyway there are all sorts of reasons drivers may not see bicyclists, starting with their not being "looking" for one. Add, poor sight lines, lack of contrast with the background, and seeing us, but not properly ranging our speed and distance.

You might enjoy this article which delves into other factors.

So, it's not a question of blame, or intentional or subconscious hatred of bicyclists, it's simply one of the realities we learn to deal with.