I think it's not a coincidence that one of Facebook's flagship partners is MercadoLibre, the Argentine ecommerce giant. Argentina's YOY inflation rate will "slow" to 34 percent this year - if all goes well.[1] The Argentines I know making monthly salaries are used to saving money in foreign currencies anyway. (HN Argentines, feel free to correct me on that point.)
Many of us live in places where we can rely on our regional currencies to remain stable. Maybe the pound will flounder under Brexit, the Euro under the debt crisis or the dollar under whatever the trade war is supposed to be doing, but there's little or no public will to divest from national currencies, and the main reason anyone would dip into cryptocurrencies is speculation. Also we're hackers and distrust Facebook. Fine - we're not the target demographic.
I think the general population of Argentina, India, Venezuela, etc etc, _are_ the target demographic. The idea would be to make savings, payments, and digital purchases for people in developing or unstable economies reliable, inflation resistant, and low-fee - particularly vs forex. As a bonus for us hackers, I'm sure every Orwellian data scraping fever dream you can imagine is rolled in too - but most people aren't hackers, so whether this is a showstopper remains to be seen.
I'm not just spitballing here - Facebook claim this to be so.[2] Thiel and Altman's Reserve Currency works basically the same way, with the same ambitions[3]. The implications are _much_ bigger than Johnny-come-latelies from Menlo Park stumbling into the blockchain hype - which seems to be the prevailing take here. What we're seeing is tech giants betting big on having total ownership over banking and purchases in much of the world's population.
[1] https://www.reuters.com/article/us-argentina-economy-oecd/ar...
[2] https://www.theverge.com/2019/6/6/18655366/facebook-cryptocu...
[3] https://reserve.org/about. Pedantic technical note: Reserve is moving in a three phase sequence from USD collateralization (like Tether / Coinbase's token) to algorithmic stabilization against a basket of goods (not currencies), whereas Facebook is skipping to phase three and using a basket of currencies as the peg. (It's an open question how this will be accomplished, since Libra's whitepaper won't be released until tomorrow.)