“Good mustard”? Nah.
Dijon has its place. So does plain old yellow mustard or horseradish mustard. None is “better” than the other. They just have different uses.
Somethings don't need to be contrasted. Especially taste! Always bugs me. Take mashed potatoes, scratch and instant. Sure they are different but it's okay to like both rather than compare them as inferior or superior.