Product management involves a lot of conflict, both within-team and between-teams. I've found the utility of conflict typically hinges on the underlying trust (or lack thereof) between those engaging in the conflict. Trust in one another as people (is this person going to screw me over?) and trust in one another’s capability (is this person competent?)

Building trust is usually much easier within teams, which is why intrateam conflict is invariably more fruitful than interteam conflict. I'm a strong believer that this is why so many orgs struggle to work effectively across programs. The trusting foundation isn't there to permit constructive conflict, meaning people bumble along in artificial harmony; achieving mediocre outcomes.