Including the British pound - until decimalisation in 1971, the abbreviations for pounds, shillings and pence were Lsd (with the L often having a single or double cross bar) from the Latin libra, solidus and denarius respectively.
Sorry. If I had explained, I don't think that it would have been unsubstantive. But I didn't. So anyway, to the point.
As the sign of balance, symbolized by scales, Libra is certainly relevant to money. But the name is also a riff on liberty/liberation aka freedom. And that's the sick joke, because Libre will be totally under Facebook control.