"Best" by what quality metric? "Not becoming an idiot" is difficult and time-consuming. Furthermore, there's no reliable way to determine if you have in fact succeeded in ceasing to be an idiot because part of the license that compilers have when encountering undefined behavior is to mask it. So even if your code compiles without warnings and passes all tests that is no guarantee that you have ceased to be an idiot. So requiring a compiler to do something more reasonable in the face of undefined behavior than reformat your hard drive (or at least to make it an option) is not an unreasonable position.
"Best" by what quality metric? "Not becoming an idiot" is difficult and time-consuming. Furthermore, there's no reliable way to determine if you have in fact succeeded in ceasing to be an idiot because part of the license that compilers have when encountering undefined behavior is to mask it. So even if your code compiles without warnings and passes all tests that is no guarantee that you have ceased to be an idiot. So requiring a compiler to do something more reasonable in the face of undefined behavior than reformat your hard drive (or at least to make it an option) is not an unreasonable position.