The dark, distressing opening section of The Last Of Us is fast becoming a 'thing' that you can show non-gamers as a way of explaining how far games have come in terms of visual and story. It's well-written, it's engaging and from a control and gameplay standpoint, it's relatively simple. In a way it's the perfect game for the Elders React YouTube series.
What's interesting about this one is the range of reactions. Some were shocked by it, some thought it was too dark. Some were openly emotional to the point of tears almost. Others were impressed by the craft of Naughty Dog's story-telling.
Either way, this video makes for some compelling viewing.