The first mistake the white couple made was to stop at the light. Then when the rock hit they should have just driven off - even if they had to run over a few of the mob.
When I was a kid (late 60’s) in the town where I lived were a couple blocks where there were stop lights. Every night the locals gathered on the corners and porches and yelled, threw rocks, tried to pick fights with any white people who stopped at the light. Then when the light turned green a few in the middle of the block would slowly walk across the street. The unsuspecting would stop and get their windows broken. The white locals (kids mostly) would just punch the gas and take off - making the strollers run out of the street.
A few got hit, and some tickets were issued, but the only people who actually got beat up or had damage to their cars were those who trusted that nobody would “do those things”.
The reporters should have driven off after the first rock was thrown. Sometimes being street smart is WAY better than being book smart or being offended that someone threw a rock at your car.