You're overindexing on formal authority and prematurely discounting informal influence. RFK will be a prominent member of the administration. He'll have the ears of powerful people. He'll get some wins at the FDA (because it's blindingly obvious we're poisoning ourselves), and he'll be able to use these wins to drive changes at other agencies.
Is the next administration really likely to do, on purpose, anything that would affect earnings for large corps? It would absolutely blow my mind. I think RFK will do zilch unless it aligns with more profits for the right folks.