In MVC, "C"(controller) must hard refereces a variable‘s name of UI elements from View. Therefore, changes in View will domino "C" code changes.
In MVVM, because of "Data Binding" mechanism, "C"(controller, or ViewModel) don‘t hard references a variable‘s name of UI elements from View. You can easily config data bindings in XAML/WPF. So, changes in View won‘t domino "C" code changes.