What made bitcoin survive is that it is decentralized. There is no central point which can be attacked and shut down.
Past attempts to create a digital currency all failed because they were not decentralized and/or because they couldn't solve double spending.
Nicely said. Good to see some lessons from the past history of cryptocurrency. Right now, when we talk about cryptocurrency the standard is of course Bitcoin and anything that is centralized like the newcomer Libra or even the Ripple we usually can say that those are not at par and should not be compared with Bitcoin with some even saying that those are not cryptocurrencies at all.