It does work fairly well for powdery mildew, provided it’s used more as a preventative than a remedy. Personally never seen it as an effective control for bacterial wilt. Once the plants are infected it’s a slow decline, and the brutal heat in peak summer when they are most susceptible only worsens it.
About the only thing that works for us is complete exclusion of the pests that carry it. Of course you have to uncover once the plants begin to flower and it’s still just a ticking clock until they will eventually succumb.
