I think that Libra should not interest us as investors in cryptocurrency. This is the same as investing in USDT. At its core, Libra will be a tool for trading on the cryptocurrency market.
Facebook libra plan to make it stable price so yes it will look like the same as USDT.
I dont think libre can be tool for trading . Libra will have their own use can be use many market will accept libra as mode of payment online which will make it more easier to people to pay. For example for in uber they can use libra instead of cash.