You have explained human behavior perfectly. It is very fascinating how we act against our own interests. We want to appear confident all the time, we want to be happy but many of us do not align with our habits with those desires. I think this comes from a mix of laziness and fear of change. Fear of failure. Fear of leaving your comfort zone. As you said that confidence and happiness come from efforts. The effort we make when we try to improve ourselves not from pretending. Everyone these days wants shortcuts to the reward without walking the path that actually leads to their destination in life.
We want to appear confident, but to do so we just try to cover up all our flaws with big clothes, makeup, and an inflated ego.