I hope you never learn to keep your mouth shut. I really value your opinions regardless of how dogmatic or opinionated. In fact, I value them so much that I feel a real loss knowing that they are out there but not shared.
(On a side note, I like you for being so emotionally involved, passionate and opinionated and how capable you are of taking control when the opportunity arises. No one should ever estimate you as the shy wall flower. You are a very powerful woman)
Do you feel uncomfortable sharing because you are afraid of being judged? Or do you worry about hurting people's feelings or do you fear being unliked or "not nice"? I ask because, I worry about the latter (hurting feelings, not being nice) as well and I think it's what contributes to lack of authenticity. Does that come from the societal requirement to be the "good girl" ? Again, projecting myself onto you so just brainstorming.
I know you will never believe me if I tell you how beautiful and intelligent you are and how superior your wealth of emotional insight is. So I will say this instead. We all come from different backgrounds and we all have different experiences. Our thoughts and opinions all have value. And we all have something to bring to the table. What we have to offer may or may not be helpful to one, but has the potential to help another. There is so much to be said about the sharing and exchange of ideas.
At the very least this is a good place to practice those skills