And the AI search technologies I used tended to not be particularly good. They typically find "background" documents that are related but can't be used in a rejection.

I don't anticipate LLMs being able to examine patents in general well. Many times a detailed understanding of things not in the text is necessary to examine. For the technologies I examined, often search was basically flipping through drawings. I'd love to see an AI search technology focus specifically on patent drawings. This can be quite difficult. Often I'd have to understand the topology of a circuit (electrical or flow) and find a specific combination of elements. Of course, each drawing could be laid out differently but be topologically equivalent... this surely can be handled with computers in some way, but it's going to require a big effort right now.