I think if a sponsor was thinking about throwing money at an older runner, she would have to have some serious podium places at some serious races.
The Vaporfly seems to be tuned for her weight and mechanics. (This is what some refer to as high "shoe responders".). If that is the case, what would be the incentive for her to leave that shoe? What is the incentive for Nike to sponsor her since she is in effect, giving them free advertisement through her performances in those shoes?