I never heard that all the transactions in the world got rollbacked after days, and I don't think it is even technically possible.
Doing that in ethereum and all the other similar currencies is as easy as pressing a button.
> Doing that in ethereum and all the other similar currencies is as easy as pressing a button.
The rollback was (and still is) very controversial. It required the agreement of the large mining pools to support the fork, which they eventually agreed to. It wasn't quite as simple as "pressing a button".
