The biggest advantage of an LLM is the interface and reading text.

Whatever we had before on full text search, LLMs are a lot better. And i'm not just feeling this, i read plenty of articles about exactly this.

A LLM doesn't need to be retrained every week, it needs to have a base corpus of the field and strategies on how to find current text. They will load it into context and argue.

Then another LLM will take this and formats it for the court.

We will see but i think you overestimate how much automatisation and co current lawyers have and use.