You call it "self-exuberance"; I call it "bragging": miscalibrated predictions of emotional responses to self-promotion.

People engage in self-promotional behavior because they want others to hold favorable images of them. Self-promotion, however, entails a trade-off between conveying one's positive attributes and being seen as bragging. We propose that people get this trade-off wrong because they erroneously project their own feelings onto their interaction partners. As a consequence, people overestimate the extent to which recipients of their self-promotion will feel proud of and happy for them, and underestimate the extent to which recipients will feel annoyed (Experiments 1 and 2). Because people tend to promote themselves excessively when trying to make a favorable impression on others, such efforts often backfire, causing targets of self-promotion to view self-promoters as less likeable and as braggarts (Experiment 3).