What is the motivation for such a measure? In other words, which problem is it trying to solve? And how it is supposed to do so?

I think that we should not carelessly invent laws that just "sound good" to some lawmakers but have no real fact checking done to support them and are not backed by science.

Because, in my opinion, then there is a high risk that these "good intentions" will backfire spectacularly. While not getting even close to achieve the desired effect.

I believe the perceived problem is that people in Utah are watching porn.