Now... would the absolute sharpest possible result be at f/8 or f/11 or so? Yes, sure. True of all formats. But for LF and some MF, that matters not one iota unless you are shooting res charts. The smoothness of the tonality and the focus transitions in medium and large formats matter a lot more (to me) than whether you can see some minor difference under a loupe.
Not to slam 35mm, which is wonderful for a great many things including some macro work, and which I also use happily, but... the transitions between in focus and OOF objects can be rather harsh in 35mm. You can see focus/defocus lines. With the larger formats, the transition from in- to out-of-focus portions is generally much smoother and more gradual.
Also, as I mentioned, a tiltable bellows gear can eke a lot more effective DOF from a wider aperture than a 35mm system with extension tubes. When I do macro with a view camera, I focus first of all with the lens wide open, then use tilts to bring as much into focus as I can, and then start stopping down, etc., if the DOF is insufficient.