I don't pay much attention to Elon's sensational tweets which are created for attention, nor is an average individual concerned with the administrative aspects of running Twitter.
Snowden offering as CEO might be a bit of crazy. But he might be able to make the Twitter more alive, Snowden must have lots of things to discuss in relation to free speech that's for sure.
A CEO does not necessarily need to draw traffic through discussions, if Twitter needed that, it would be better of going for an influencer. Also, the success of a business, even a social media platform, is far more than building traffic and engagements.