Confidence is the alief that you have high value, and it induces confidence-signalling behaviors. People judge your value partly by actually looking at your value, but they also take the shortcut of just directly looking at whether you display those signals. So you can artificially inflate your status by having incorrect confidence, i.e. alieving that you're more valuable than you really are. This is called hubris, and when people realize you're doing it they reduce their valuation of you to compensate. (Or sometimes they flip that modus tollens into a modus ponens, and you become a cult leader. So it's polarizing.)
But it is a prosocial lie that you should have incorrect underconfidence, i.e. that you should alieve that you have lower value than you actually do. This is called humility, and it's prosocial because it allows the rest of society to exploit you, taking more value from you than they're actually paying for. Since it's prosocial, society paints humility as a virtue, and practically all media, religious doctrine, fiction, etc. repeatedly insists that humility (and good morals in general) will somehow cause you to win in the end. You have to really search to find media where the evil, confident guys actually crush the good guys. So if this stuff has successfully indoctrinated you (and if you're a nerd, it probably has), then you should adjust your confidence upwards to compensate, and this will feel like hubris relative to what society encourages.
Also, high confidence has lower drawbacks nowadays than what our hindbrains were built to expect. People share less background, so it's pretty easy to reinvent yourself. You don't know people for as long, so you have less time for people to get tired of your overconfidence. You're less likely to get literally killed for challenging the wrong people. So a level of confidence which is optimal in the modern world will feel excessive to your hindbrain.
Or sometimes they flip that modus tollens into a modus ponens, and you become a cult leader. So it's polarizing.
Care to explain what they flip exactly?
I've seen the advice "be (more) confident" given so that the person may become more socially successful. For example self-confident get more raises. But I'm not sure if self-confidence is the cause of becoming more socially successful, or the result of it. I don't think self-confidence can be separated from social status. I see it more as an intersocial function that gives information to participants on who to follow or listen to, and you can't act fully confident in isolation with others and their feelings. Artificially raised confidence sounds really hard, and if possible it sounds more closer to arrogance or delusion and real confidence must have some connection to reality and knowledge of what kind of value you provide. I mean, delusion might work if those around you are delusional too, but that seems pretty risky and surer way is to just be connected to reality all the time. If what you're saying is not true or interesting, then it's hard to be confident when you're saying it and others will usually quickly notify in one way or another if what you're saying is not true or interesting. If the truth is that you can't really provide much value, then I can't see how you would be able to feel as confident as those who provide more value (note that value might sometimes be quite complex and not the first thing that comes into your mind, inept dictators might provide the kind of value that really makes sense in evolutionary context even though they seem to do nothing useful at all in reality)
So in short, self-confidence usually seems approximation of what kind of value you provide in the real world, where value is to be thought of as something that is beneficial in evolutionary context. There are some hacks to quickly raise your value, like dressing better or working out, but ultimately it comes down raising your value in the real world and confidence must follow that and not the other way around.
Thoughts? How does "fake it till you make it" strategy appears in this context?