I would like to play devil's advocate
From this article I read
Unlike the volatility seen around other cryptocurrencys in the past, we believe that Libras focus on creating a stable, low inflation currency backed by a reserve or real assets is a differentiator. Further, unlike other stablecoins, Libra will not be pegged to one currency but instead a basket of assets ranging from bank deposits to short-term government securities.
https://www.cnbc.com/2019/06/18/the-difference-between-bitcoin-and-facebooks-libra.htmlWill Libra Coin bring Down Bitcoin's dominance in the market, your thought?
Nope I didn't beleive that speculation we ahould know that libra is powerful coins in the future because the support the facebook company the devs of the new expensive coins in the duture.
But I still strongly believe nobody can overtake for bitcoin as king of crypto, bitcoin and libra are have own indentity as virtual currency.