It reminds us to get over ourselves and get on with life. “Lighten up", some call it. “Focus on what truly matters”, others say. Neither is wrong, but what happened that made us take ourselves so seriously?
Experiencing emotions and feelings is one reason. They bring our focus back to ourselves because we are at odds with the people and things around us.
There is a difference between indulging in our feelings and emotions versus recognizing, embracing, and processing them. The former keeps people in the mix of energy, while the latter encourages us to take care of ourselves and then move forward.
“Don’t take ourselves so seriously” is saying: don't let feelings and emotions stop us from being our centered self and see the possibilities beyond.