Good thing for Mark to decide quickly on this issues about Libra project, because if he's going to continue those plans inline with this Project; conflict may arise. With that resignation of all potential supporters of Libra, this really showed a non commendable signs which also intercepted in advance by the Government of USA. Their impression is quite defensive to the countries personal interest on the crimes that might occur eventually when Mark's Libra will be launched.
I don't think Mark gave up on Libra. I personally think this is their strategy to escape from fine from US government. USA never gonna accept cryptocurrency because the nature of cryptocurrency...
BTC and other altcoins are rival for US$ at the end of the day...
If they accept crypto, they cannot print money again as their wish.