If Biden were to resign the Presidency, Kamala might get a short-term bump in the polls with all the media celebration of her as the first female President. But there is no way they can control her public appearances enough to keep the public for seeing what a moron she is. The last four years have been a disaster for the country and all she can do is shriek about abortion and about Trump being a threat to democracy.
They can’t do a “basement” strategy with Harris.