People who bash the notion of American Exceptionalism do not know what the concept is. They think it means that Americans are better than other people. This is of course a bastardized teaching of the Left.
What American Exceptionalism is is the fact that before America, every single country had as its organizing principle that their populations were subservient to the apparatus of the state.
American Exceptionalism turns that on its head. We were the very first nation in human history to codify as an organizational principle that the individual had a place of unassailable primacy over the power of the state. The individual and their God given right to freedom trumps the state's power or desire to take that away.
So next time someone wants to bash American Exceptionalism, know that you are fundamentally wrong in your understanding of it. If you still want to bash it knowing what it really means, then you are a statist and frankly evil.