Id argue its already even greater. The amount of botting and astroturfing happening now means that a good chunk of the content people are consuming on those social media sites is generated by LLMs. Social media is the vector, but its the content thats the virus and OpenAI et al control what that virus contains
That's a really good point. Even if social media is and remains the medium over chat assistant apps (likely imo), all the content everywhere will be AI slop.