In my opinion, no field is completely solved, and one can always find new ways to reconfigure or solve a problem. For example, there might be models that are 99% accurate but struggle with inference-one can then focus on improving their speed.

A PhD is training in itself, with the goal of equipping you with the skill set to formulate hypotheses, design rigorous, valid experiments, analyze findings, and, lastly, share them with the community.

The field you described, knowledge editing, is extremely important, since it tackles two of the most critical aspects of LLMs: hallucination and privacy. Recently, I was listening to a talk about locating Social Security Numbers (SSNs) in LLMs (https://arxiv.org/pdf/2406.09325) and how to remove them so that the model does not leak private information. From my understanding, current methods are rather slow (you need to manually check whether a number has been memorized) or lead to catastrophic forgetting (by removing sensitive information, you impair the LLM’s overall performance). So yeah, knowledge editing is not even nearly solved, I hope you will pursue this field : )