An elegiac broadside is A MOURNFUL, PLAINTIVE BALLAD
An elegy is a poem of lamentation to mourn the loss of something or someone. And broadside can mean a verbal attack. So the definition, a mournful, plaintive ballad fits best here.
Only if it is NOT shown while someone is driving.
Actually, it CAN affect people if the message is presented in a way that truly causes people to see themselves in the situation.
: to make (someone) rich or richer. : to improve the quality of (something) : to make (something) better. : to improve the usefulness or quality of (something) by adding something to it.