Nit: Genocide isn't about numbers. And watching reels isn't dying, at least not in any other sense than an existential one.
1. this level of preoccupation is a new and historically significant phenomenon
2. the time not spent on scrolling would be spent on something else more productive
Both seem plausible, but they also seem like a couple of those tricky conclusions that seem naturally right but would fall apart with some research. For example, I think it would be better if we all spent time at cafes instead, but it's hard to say that that would result in better societal outcomes.