A better anology would be a virus. In some sense LLMs, and all other very sophisticated technologies, lean on our resources to replicate themselves. With LLMs you actually do have a projection of intelligemce in the language domain. Even though it is rather corpse-like, as though you shot intelligence in the face and shoved its body in the direction of language, just so you could draw a chaulk outline around it.

Despite all that, one can adopt the view that an LLM is a form of silicon based life akin to a virus and we are its environmental hosts exerting selective pressure and supplying much needed energy. Whether that life is intelligent or not is another issue which is probably related to whether an LLM can tell that a cat cannot be, at the same time and in the same respect, not a cat. The paths through the meaning manifold contructed by an LLM are not geodesic, they are not reversible, while in human reason the correct path is lossless. An LLM literally "thinks", up is a little bit down, and vice versa, by design.

Clearly the number of "brain cells" is not a useful metric here- as noted also by Geoffrey Hinton. For a long time we thought that our artificial model of a neuron was capable of much less computation than its biologic counterpart; in fact the opposite appears to be true- LLMs have the size of a tiny speck of a human brain yet they converse fluently in tens of languages, solve difficult math problems, code in many programming languages, and possess an impressive general knowledge, of a breadth that is beyond what is attainable by any human. If that were what five cm3 of your brain are capable of, where are the signs of it? What do you do exactly with all the rest?