In decades of serving as a rabbi, I cannot tell you for sure which phenomenon in the synagogue is most commonly helpful, but I can tell you which is the most commonly destructive: the assumption of ill will.
Disagreements are expected. Even arguments can be salutary. God knows the Jewish people have a decided tendency to argue. But the belief that the other person is advancing a position because they are driven by nefarious motives contributes to the deep divisions within communities.
The issue can be about masks or about minyan; it can be about staffing or about schooling; it can be about Jewish law or parking spaces. No matter the seriousness of the question, if you believe the person opposing you has the best of intentions, it changes the argument and often, the outcome. If on the other hand, you are convinced that any decent person would think as you do, you will be unable to overcome the divisions that any community inevitably faces. I’m not asking you to agree with me; I just want you to believe that I am not evil for disagreeing with you.