(Thread.)
Can potentially introduce cryptocurrencies and digital wallets to 100s of millions of people (vs ~50M).
They can turn every Facebook, Whatsapp, and Instagram account into a savings account.
They modified HotStuff instead of other options because of a cleaner separation of safety (voting and commit rules) and liveness.
Facebook is using existing users with a path towards decentralization. Blockstack is open and permissionless and will always be.
There are many upcoming challenges: (a) switch from permissioned to permissionless, (b) earning the trust of developers, and (c) conflicts with the Facebook business model.