Online written communications will never follow the same patterns as direct communication, and that is a good thing.
My self esteem has also been heavily based on believing that I'm really smart, but I never had a problem admitting I didn't know something. "Smart" to me means my ability to learn, problem solve, and make connections.
One of the most significant factors in my success to date has been my almost eager willingness to admit my lack of knowledge, and to ask others to share their knowledge.
How else are you going to learn new things?
Even the very word discussion comes from late Middle English (in the sense ‘dispel, disperse’, also ‘examine by argument’): from Latin discuss- ‘dashed to pieces’, later ‘investigated’, from the verb discutere, from dis- ‘apart’ + quatere ‘shake’.
We generally don't do a very good job of talking about things in way that brings those things, or us each other, closer together.
Very often, English-language experts can appear to defeat subject-matter experts in debates. When this happens it's usually because of footwork on the "language layer."
I remember the good old days, before the internet, when people would always admit their ignorance in real life and the Dunning–Kruger effect didn't exist.
Their system isn’t too bright.
But I'll often bookend a comment like that with points about what I don't know. And here, there are points I think someone might know - frame those as questions. But also there are point I doubt either myself or the person I'm replying to knows, frame those as problems of knowledge, statistics and so-forth.
Obviously, I think I know a general framework, that our beliefs are areas of semi-certainty bordered by heuristics, myth, ignorance and lack of awareness. But this is a belief that will often about what I or we, don't know.