that's a good point. LIBRA is going to be one of the rare projects that is decoupled from BTC so it won't have any direct affect - but at the same time it will kick out competition like USDT which is directly connected to BTC... you are right, very hard to say how this will affect BTC

Probably negatively in the long run, but it will defiantly help stabilize the whole market and and bring us 1 step closer to being a mature market.