Passage Summary: Even though video games have been selling well lately, the author thinks sales will drop because there will be fewer teenagers around, and they are the ones who buy most of the games.

Conclusion: The recent trend of increasing video game sales is expected to end soon.

Reasoning: The primary demographic for video games, teenagers aged 13 to 16, is projected to decrease in size over the next decade.

Analysis: The author is betting the house on the idea that if the number of teenagers drops, sales must drop too. To weaken this, we should look for an answer that suggests other groups might start gaming more or that the remaining teens will start buying way more games than their predecessors did. Perhaps the 'aging gamer' isn't just a myth, and 30-somethings are finally putting their disposable income to use. If the customer base expands beyond that narrow 13-16 window, the author's prediction falls apart.