It's closer to a 'helper' than what you're suggesting. There's no instability whatsoever in level flight, at least relative to other planes. The issue is that

It's closer to a 'helper' than what you're suggesting. There's no instability whatsoever in level flight, at least relative to other planes. The issue is that the large surface area of the engine nacelles is far forward of the plane's CoM. The effect of this is that the control stick becomes 'lighter' as you approach high AoA. This is considered acceptable - though not ideal - in many aircraft, but would have changed the pilot rating requirements from the old 737s. Some people seem to be suggesting that this is some sort of advanced stability system; the reality is that this is just an automated trim adjustment. Clearly it's very important, but the idea that the plane couldn't fly at all without it is absurd.