You're thinking of SM-3, not SM-2, and SM-3's minimum altitude is somewhere in the rarefied upper atmosphere when it burns out and can separate the kill vehicle. Not even the abortive SM-2 Block IV was hit-to-kill.

That said, all SAMs without nose proxy fuzing are /theoretically/ capable of directly impacting their targets. Only a scant handful of ABM-specialized interceptors are designed to do so in order to ensure either complete warhead destruction OR a miss that doesn't produce a boatload of shredded debris clutter.

A direct hit would shred a huge amount of of the airplane, the expanding cloud of non-warhead missile bits would blow a hole through the other side, and the entire thing would be LITTERED with shrapnel.

A marginal intercept is unlikely; you'd need the missile itself to fail in some way; airliners are, unfortunately, effortless targets. Even then, it would have to miss by an absolutely humongous distance (probably larger than a proxy fuze could measure, so command-detonated by the launching system) to golden BB one single piece of shrapnel into a vital airplane bit.

There are a nigh-infinite number of ways anti-air engagements can go, but virtually none of them result in splashing the target without poking a telltale quantity/distribution/shape of holes in it.