I'd like to believe hi-viz clothing in the day is beneficial, but I have a lot of evidence to the contrary. It seems you could be wearing a bear outfit and the folks who are looking for large vehicles or engaged in searing dialog on their phones... these folks probably won't see you.... so don't get too optimistic and be certain to ride defensively.

However, I am in favor of reflective strips in the night... along with reasonably bright lights.

https://www.youtube.com/watch?v=eaETt7hQ6AA