Current mainstream social platforms seem to be losing their edge. The golden age of broadly public networks might already be behind us, with a clear shift back toward closed communities—group chats, forums, niche spaces. What's more concerning is the timeline: within 1-2 years, AI will likely become sophisticated enough to infiltrate even these more private channels in ways that even AI specialists won't easily detect. This convergence of platform decline and rising AI risks could fundamentally reshape how we think about digital communication and security.