CliffordK

I hope that isn't driving from Mississippi to Los Angeles in an afternoon.

I can't discern the difference between your 30 min and 15 min photos. Same 3 vehicles ahead, from both directions?

Nonetheless, your first 3 photos prove your point that a cyclist that would be along the left shoulder would be difficult to see along the entire length of the shoulder. Of course in those photos the sun is more to the left.

And in the last photo, the right shoulder begins to wash out. There is a merge sign pole in the last photo that is difficult to see clearly. Likewise, a bicycle 100 feet in front of that merge sign might be invisible.

I can see the visor down in most of the photos.

As the sun descends further, it is possible it could become worse.

Also note the tree line that can give a significant benefit. It may well be different in places without a tree line.

The middle of your windshield looks clean as if it has recently rained. It is possible that parts of the Southwest haven't had significant rain for some time.