Edit: here is my take on it + the most likely scenario of what's going to happen next. This was a bad deployment and such things are not unusual in software industry. In this specific case, there are zero reasons to blame the CTO. From what I'm observing right now, Twitter has already fixed the issue - the website loads just fine. Next, they will do a retro, learn from their mistakes and try to not repeat the same mistakes again in the future. There will be more bad deployments and that's normal. However, with time, they'll make things better, the SLA will go up and the overall stability of their services will stabilize, – one of the biggest social networks on the planet will have the least number of engineers running that same social network.
The point of a decision-maker is to make informed decisions, if you fail to do that, then you fail at leadership.