LeCun is a lot more than a "Grey Beard"... lol, that is a significant understatement of his contributions to the field and position in the field.
Among other things, LeCun is one of the senior people industry who has a deep understanding of the mathematics and analysis underlying neural networks and "neural network like" approaches to machine learning. I think he understands a lot more about neural networks than most researchers today.
I also don't think our current LLM models are AGI and think the LLM approach is, mathematically, incapable of producing an AGI. At the end of the day, the architecture is still a streaming token plinko machine with a lot of guide-rails to achieve good behavior.
I do think it is very impressive how far hundreds of billions of dollars have been able to take LLMs in terms of usefulness (I use LLMs everyday in my job). AGI or not, current LLM models are a pretty incredible achievement and will provide lasting benefit even after the economic implosion of the AI industry occurs (which I think is imminent).