We are comparing a stale crypto currency with bitcoin.
Both uses blockchain but the coin from facebook is centralized so it is not an alternative of people think fiat money is not needed in future.
but in the future also requires digital assets that have a stable value. bitcoin and many altcoins have very fast changing values depending on market demand. then what are the assets like this that we can use for payment in the future?
Libra will develop for the basics of the concept of using their coins. and bitcoin and other altcoins will remain crypto traded with the uniqueness of this market.
Stable = centralized,so we are giving the control of our money to someone like the old same traditional banking system.
This is not the actual vision of satoshi,even if the price is volatile its on the own demand no body control over it which is the best for future.