Don't think I could disagree any harder. Requirements change. Business needs change. You want your FE to be able to evolve independently without having to wait for the BE to implement the precise logic you need.
As well as your FE team forced to wait on BE changes for new features, you've also created busywork for the BE team anytime there's a FE refactor/restructure to boot.
An organisation that separates frontend and backend teams will naturally converge to an architecture where the collaboration between frontend and backend is minimized (i.e., a generic REST API) -- Conway's law.
This doesn't mean that an actual cross-functional team that contains both frontend and backend developers can't use the proposed single-purpose API to run circles around the split team.