Is it better to talk about and share opinions or keep them to yourself?

My answer will differ based on the circumstances. It is crucial to share opinions if it constructively helps others. For example, I would share my opinion if it would be helpful to others or myself. Indeed, the premise would be the open-minded conversation. In comparison, I would keep them to myself if my opinions were too sensitive and offend others greatly. This conversation will eventually harm the relationship and hinder the opportunity to further necessary dialogue. A Japanese colleague in my team shares politically sensitive remarks, and no one, including me, does not want to talk with him other than at work. I believe the casual conversation will foster creativity within the team, but his attitude stops this collaboration, which hinders efficiency.