Wow. That is a beautiful commercial -- which utterly transcends the particular UK locality it was originally targeted to -- and remarkably different from typical PSAs of this type. (Indeed, fearing the typical scary PSA, I almost didn't click on the link.)

Apparently it was designed that way:

Created to raise awareness of the importance of wearing a seatbelt, Embrace Life was deliberately developed to provide a counter-point to the hard-hitting 'shock and awe' advertising so common to road safety.