I think listening is important, but so to is remaining politely sceptical and maintaining appropriate humility (self scepticism). Demonstrating too much certainty can be a sign of someone who thinks they are smart but they are not. If they want to present confidence, they should do so with evidence, and not be too quick to be sure of something.
Also just keep asking questions, you can often say what you want within your approach to asking questions, but if you are not seeking information, and prepared to change your mind you could not possibly be smart.
It's me, I'm the problem, it's me! I'm the awkward person who tries too hard to seem smart! At least, that's how I seem to come off typically... I think it's because I can't seem to shut up :D
If you want to change that I can give you a tip. It is great if you apply what you heard to yourself. But that should be done on your own or among your friends. If you are in an other environment try put the focus on other people or on things. That way you can talk just as much while appearing less try-hard.
"An intelligent person always wants to have all information first so then they can analyse it and respond appropriately." - Yes, an intelligent person... or an anxious one. 😅
The wait and listen sign is not necessarily true. There are a lot of people who just like to talk and are very predictable and/or shallow. Also a lot of people rather share their own ideas instead of hearing a better one that a different person may have to offer. People who are on an other level of smart find listening to most people repetitive and boring. They listen out of politeness, not because they expect some new information. They also may stay quiet because they don't expect the other person to be interested in their opinion. And even if they were, the smart person may not have the desire to seek validation given by a person who is considerably less smart than them. To me it seems like you describe the smart people in social environments and jobs. I come from a technical background. There being smart is shown in different ways. Curiosity, considering all information and having a goal oriented methodology are signs of smart that are applicable to all backgrounds. But being witty or making other people talk is not. In the technical fields really knowing the basics and the nuances, a wide range of knowledge, coming up with creative ideas and being known and respected by a lot of people in the industry are better signs of a really smart person. I like to distinguish between smart and intelligent. Smart is the overarching term that also includes wit, emotional intelligence, being able to memorize and so on. Intelligence is just IQ. I noticed that intelligent people are quickly bored if things are repetitive. They are quick to learn and understand. And they are also good at seeing patterns which other people are not aware off.
I think a lot of us have the fear of not being smart enough and it gets triggered - I know I do! It's difficult not to feel personally targeted if something is on the list that we're not doing - I feel like an idiot most of the time, to be honest, regardless of what others tell me. But, it might be that my social skills could need a polish!