Other people seem to be able to sit down and assimilate themselves into a group conversation, when I do this I rarely end up saying anything.

Yeah, I think that feeling unconfident is largely the cause, so it's something that I should try to avoid even though it is an especially poor internal signal. I should try to make myself update on some more reliable signals like those.

Yeah, I should try that more. My main issues with mimicing successful people is that I have trouble mustering the emotion to do it effectively.