Give this a day to settle. There's a lot of misinformation out there.

NYT: "Its landing gear appeared not to have dropped down from under the plane, and the flaps on its wings apparently were not activated for landing, Mr. Tonkin added. “The aircraft was essentially in a flying configuration,” he said. That meant the plane was likely “flying faster than it would normally be in a landing situation.”"

That's consistent with the video. The aircraft is sliding down the runway, lined up with the runway, going too fast, wheels up, flaps up, possibly still under power.

"Why" is days away.