Modern AI started with NLP, computer vision and speech recognition and it was expected as chips get more powerful and faster, that software and AI people would figure how to utilize the massive new computing capabilities. My prediction would've been early 2010s for something like LLMs to occur but I guess I am too optimistic. And probably if it wasn't for Google and their enormous spending on R&D we would see LLMs not in early 2020s but in early 2030s.