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?
Well, if it actually ever launches yeah probably it will bring it down, perhaps by a lot. This isn't necesserily a bad thing, and probably it will help the price of BTC skyrocket. Reason is simple. Many everyday people that hadn't touched or even knew about cryptos before will get their hands on someLibra, and a substantial part of them will probably diversify into other coins, with BTC being the top one. IMO, libra could be a deciding factor to mass adoption!