My dictionary tells me that "hubris" means "a great or foolish amount of pride or confidence." An equivalent in Spanish would be "arrogancia, presunción."
The definition and the equivalents would appear to be negative traits. Who cares about arrogant and overconfident people?
However when we approach the language experience we need "hubris," the confidence, the "presunción" that thanks to our motivation, efforts, time, study and patience we are able to communicate with others in the target language we are trying to master.
Do not fear making mistakes, mispronouncing words, using faulty grammar... With hubris you will be able to practice and communicate. Remember that those who do not make mistakes, make nothing.
Have plenty of hubris when using language... and learn all the time.
Nobody is going to laugh at you... after all, you communicate with natives thanks to your efforts, not theirs.