Meh. Not a smoking gun.
I don't support Kavanaugh - these memos aside, his general disrespect for 4A issues, his boot-licking worship of executive authority, and his participation in the crafting of the so-called "PATRIOT" Act make him unfit to even set foot in the Supreme Court building, let alone sit on the bench there.
That being said, the memo is pretty damned vague. It could very easily been a response to various hypothetical questions. No point in dreaming up and being distracted by conspiracy theories when there are mountains of substance to work with.