People drive cars every day, isolated in a box with windows rolled up, playing music or radio, not being able to hear what's going on around them. So I don't buy the safety argument of noise canceling headphones being dangerous.
That said, the masses have had noise cancelling earbuds for years at this point and while there definitely are cases of people getting hurt or killed from being unaware of their surroundings, it’s not really been that big a deal.
Firearms have been the leading cause of death for people ages 1-19 since 2020.