The only negative side to libra for me is the government interference and control that they are demanding and in the end it will not be a surprise to me if libra comes up as a centralized product with probably every transaction taxed which can hinder its free use, otherwise everything about this project is positive and huge in terms of its global impact.
Interference and control or management from governments occur not only with Libra, but also with bitcoin, and other altcoins or tokens, especially with crypto currencies that focus on user privacy. Because governments basically don't want crypto currencies to be used and compromised as good tools for money launderings.