The witness are elected by the steem user and have the power to vote for a new hardfork. So when HF20 was announced, every witness has to decide to install it or not. When a defined percentage of witnesses did go to HF 20, it was activated. Normally, this should not be a problem and the new features are then activated on the scheduled date.
This time, there were two undiscovered bugs, one in HF 19 and one in HF 20.
After the crash, the elected witnesses have the duty and the power to recover and to start the steem chain again.
I do not see, why this is not decentralized?
Because whole community have to decide who are those 20 centered witnesses. Those twenty are centralised power and decide what to run for whole network.
We should rearrange votes on them if they fail like yesterday.
Vote for @abit!