LLMs can't learn. It's one of their inherent properties that they are literally incapable of learning. You can train a new model, but you can't teach new things to an already trained one. All you can do is adjust its behavior a little bit. That creates an extremely expensive cycle where you just have to spend insane amounts of energy to keep training better models over and over and over again. And the wall of diminishing returns on that has already been smashed into. That, and the fact that they simply don't have concepts like logic and reasoning and knowing, puts a rather hard limit on their potential. It's gonna take several sizeable breakthroughs to make LLMs noticeably better than they are now.

There might be another kind of AI that solves those problems inherent to LLMs, but at present that is pure sci-fi.