Where to begin. This article is full of big words and drama. I've been reading through the whitepapers and discussions and there seem to be an awful lot of people reading all sorts of things in this stuff. What worries me is that it mostly is people responding to interpretations rather than the raw facts. Big dramatic outcomes make for awesome blog articles. But that doesn't mean it's the only outcome; or even the likely outcome.
I try to look at this a bit more rationally. Given that blockchains have grown economically in the last few years for reasons that you may or may not agree with philosophically, morally, etc., it is not surprising that existing entities with economic wealth are looking to get in on the action. From this point of view, what Libra is doing is entirely unsurprising.
From a technical point of view, what Facebook is doing with Libra is cherry picking what seems to work in the market. Consensus models seem to work for the likes of Ripple, Stellar and a few others. There are a lot of people who object against this model for all sorts of reasons. But it undeniably works and scales quite well. A system this ambitious needs to scale. It's not optional.
I don't really see how Libra could have picked anything else given the current state of the art. Mining seems a dead end in terms of scalability and off by orders of magnitude from where it needs to be. There are lots of technical issues and even when it works, things like 50% attacks, insane energy consumption, etc. make this a non starter. Ethereum has been trying to switch to proof of stake for some time now and the are also trying to introduce sharding. Maybe this is fixable, but the reality is that they are nowhere close to shipping something that scales by the time Libra intends to open for business.
So, when Facebook decided to do this, building their own platform was a foregone conclusion because what's out there just isn't anywhere near good enough and basing it on consensus algorithms was the only logical choice technically.
The only relevant question is, why is it just Facebook doing this and how long is it going to take for the rest of the world to react? I'm talking about the likes of Google, Apple, banks, the oil industry, anyone with economic resources basically. They'll all want in on the action and not all of them are going to be inventing their own blockchain like platform (using the term loosely here). I doubt they are going to have Facebook have all the fun.
The follow up debate about the legalities and regulations is also going to be interesting. My guess is governments will react slowly and by the time they start making bigger decisions, it will be too late. Once you have a few "too big to fail" type companies doing stuff like this, they are not just going to pull the plug.
So, I expect things will heat up shortly. I think this is a good thing. We need competition of ideas and approaches. If what Libra is doing bothers you, stop whining and do something better. Now is a good time to get started with that.