I assume that is exactly for one of the reasons they mentioned in the article: increasing costs for sms

There is a difference between mirror like reflection and diffuse reflection. Mirror reflection is what you get with metal roofs which beam the sun directly to a target resulting in one spot being blinded. Diffuse reflection will spread it around, resulting in more light all around which is what we can handle as humans.

Most cows eat soy which is produced on former rainforest grounds.

Additionally, we are better off eating/using what is produced on farmlands directly instead of feeding it to animals. That is much more energy efficient!