Indeed, "It was terrorism" is a nice, open-and-shut case. Nobody above a certain pay grade gets blamed and nothing gets improved. Even better, such claims can motivate other kinds of political and economic decisions. It's very convenient.
It's right up there with those other news commonplaces, like "Airplanes don't just fall out of the sky." Yeah, they do, but very, very rarely. You're looking at an event that "just doesn't happen." So what, among all these unlikely scenarios is the most likely?
Making it worse is the ratio of media exposure to data available. It's always been bad, but since CNN discovered that MH370 doubled their ratings, "aviation crash mysteries" command worldwide attention. The lack of data is actually an advantage, since television news bits don't like to go over 30 seconds these days. The enormous pressure means that people who have even less knowledge than many of those posting here suddenly find themselves in a position of power with respect to news outlets. And we get ignorant "leaks" about bombs and right turns. At least the idiot who said it had to be an explosive was honest about his grounds for thinking that.
So all we have at the moment is a field of wreckage and a series of ACARS messages, transmitted over a couple minutes. Now, those messages could mean anything. What they do say is "electrical fault, smoke in the lavatory, smoke in the avionics bay." And, if you were not to posit anything else but those messages, you'd expect the people up front to start shedding non-necessary electrical systems.
As we've seen, an Airbus, at night, in Alternate Law is already a challenge for some pilots. The rest is a balance between how bad the situation was and how badly it was handled, and we cannot know that at the moment.
As for causes of the message: iPad batteries and bombs are at the bottom of the list, just below spilling the cologne on the O2 supply.
Oh, and the sideshow about alcohol? Yes, alcohol is an accelerant, but a pretty poor one, even at 95%. Sure, it's burned teenagers' faces off before, but at normal concentrations of oxygen, it just doesn't generate enough heat by itself to be useful for starting fires.