They mean even less if a causal link isn't established, or even if there is a link but the issue is better explained by other factors. There are many signs people use social media to compensate for something missing in their lives (such as lack of connection, inability to find like-minded people close by, etc.), but no proof I've yet heard of that it's the root cause of unhappiness. The closest to that is maybe people falling into maladaptive patterns of seeking content that would enrage or depress them, but I imagine at least as often it's going to be people using it as an escape from a difficult reality. We should be discussing why reality is so difficult to manage and in more extreme cases, why talking about mental health issues is so scary that so many people need to escape via alcohol, drugs, screen time, etc.