I can find you many exceptions where globalization has made peoples lives worse. However, on the balance, it has bettered conditions. Note that those countries that have shut themselves off from the outside world are among the poorest. Think of China's example. It was closed to the outside for hundreds of years and the result was a greatly weakened China. The Tang dynasty was among the most successful and it distinguished itself by the extent to which it was willing to accept outsiders, compared to its neighbors.

I definitely think it has helped people's languages, in the sense that there is more communication between different countries, and therefore more interest in learning foreign languages.

Advanced telecommunication, easier and quicker transportation and global media made the access to different cultures and their languages more intense. Even if one is not intending to learn a new language, one is exposed constantly to many spoken tongues. You will find more and more words from one language used in the conversations of people from various countries,which happened in the past as well, but not as intensive as nowadays due to the profound effect of globalization on such a phenomena. However that doesn't mean there would be any tangible improvement in any language one is learning without a pursuit of advancement associated with the required efforts.