Block chains are not a fix all solution to every problem man has... Completely unmoderated SM will of course end up being abused for profit or agenda's etc. A censor resistant, borderless block chain SM will end up being a steaming pile of shit like 8chan or steemit by design.
Not only that, but why/what incentive does a private company have to even use a public blockchain?
Answer: They don't even want it. That's letting the miners have the profit. And they won't do that. They'll have the chain in the existing company servers, same old top down management of the past.
I mean we all know the reason that anyone would want to operate a global currency like this. It would be so they'd be able to make the interest on the money that is beind held on the platform.
Lets just say they have $10 in reserves and invest it in US treasury bonds -- which is probably all they'd be allowed to do within regulatory issues. So they'd be making about 300m a year on people holding their money and transacting on the network as everything would be onboarded with peoples USD. Sounds nice right?
Where did you get that idea?
Re think that as motive. Consider a currency that geo-locates you, knows your habits better than you, and knows all your friends and associates.
Taking a simple binary case, you and your friends are split into believers in political party A and B. It's Saturday. You are undecided on A and B. Various of your friends are out and about. FB favors B.
Friends (B) 11,13,15 receive notes for a discount on Starbucks, a location half way between where you and they are. 11 goes, then 13 and 15 get a note he's there. As do you. Friends (A) 2,7,9 are closeby, but get a prompt from FB of a sale at the mall in the other direction.
You spend part of your Saturday chatting with (B) people.