Seemingly low I’d think. On the bike bus they’ve got hundreds of kids and parents around them and a police escort, so it’s not a normal biking situation. Plus parents likely are teaching kids bike safety.
Biking in this bus formation and biking normally are separate enough that it doesn’t seem to be a concern. IMO that’s like asking if kids don’t where seat belts on a normal bus, are they then at risk of not wearing seat belts in normal cars?