People with extreme political attitudes are often assumed to be more resistant to change than moderates. If this assumption is true, extreme attitudes would ossify and continuously aggravate intergroup conflict and polarization. To test this assumption of stubborn extremists, we use large-scale panel surveys of attitudes towards policy issues and general ideologies across up to 13 years (combined N = 16,238). By tracking the same people across multi-year periods, we are able to ascertain whether extreme attitude holders exhibit less change in policy attitudes than moderates. The results revealed that extreme attitude holders are more likely to change their attitudes than moderates across various policy issues and general ideologies, and tend to directionally moderate over time. A final experiment finds that lay people incorrectly believe that extreme attitudes holders are more resistant to change, contrary to the results found here. We discuss the implications of this finding for understanding the evolution of extreme attitude holders, the misperception of ideological and policy differences, and the role of inaccurate out-group perceptions in shaping polarization and intergroup conflict.