No, clearheaded, I don’t think anyone becomes less equal. The question is whether the term equal is the right term in the first place. Is the President “equal” to the Vice President? As a human being, absolutely. In his function as Vice President, absolutely not. But like you said, if the President becomes incapacitated, the VP takes over his function.
I do think a wife should “enlighten” her husband when appropriate, but not c”v “going against” him.