I don't think so, there is no way it would achieve mainstream adoption if there was a potential tax liability for users spending their after tax dollars.
The only press coverage I see about Libra is how governments are not gonna let this run and a bunch of other negative remarks (possibly drawn from the fact that this is a Facebok project which is seen as am evil company by many).
I don’t understand how is that valuable? If that’s valuable then all companies with bad press would increase their valuations. Unlike the popular saying there’s actually such thing as “bad press”.