Sorry I can't watch youtube where I am. Is there 22 kV AC equipment within the height of pantograph?
Lockie91 is thinking of other cities where the electrification uses 22kV AC. Victoria uses 1.5 kV DC. Still enough to kill passengers if they touch a live wire while wandering around.
The real problem for the passengers is that there is no incentive for the operator to evacuate the trains. The passengers can be 'safely' left there for hours, albeit in considerable distress. But distress is not going to cost the operator anything, while the resources on the ground to evacuate quickly will.
So, they first have to work out what is wrong, then get the staff to travel (through peak hour) to manually open and earth the remaining overhead, and ensure that all trains are stopped so that there is no encroachment in the dead section. An hour if you're lucky.
Then they have to get staff to the trains (again through peak hour) to evacuate the passengers and safely sheppard them to an access point. That takes a while - think of getting people with 'special needs' down to track level. Probably only a few teams, so they do it train by train. Tough luck if you're in the last train to be evacuated.
And, of course, if the media or the government asks questions about the length of time, the media spokesperson intones 'safety', and everyone says 'that's alright then'.
It's somewhat ironic that this fault must have occurred pretty much outside electrol.