I'm not sure this is always the best approach. You should not vent, clearly; and it takes two to tango. However, some concrete and professional differences in opinion do matter. This could be an opportunity to express how you deal with such a challenge. You might explain (without revealing proprietary information) a difference of how the company's (new?) direction diverged from your professional path, how you informed the organization with an open mind, evaluated options and collaboratively decided it was time to move on, with sufficient notice and transition assistance.