Never underestimate human greed.
If Satoshi or somebody close to him will ever have access to those keys, we will eventually spend.
I think that Satoshi is either dead (which may make a certain clown's actions make some sense), either have completely and deliberately destroyed those keys.
Just one thing not to underestimate. The human instinct for survival is a really, really strong motivator. Gun to the head? Gun to family's head? Deus ex machina situations where money is the only solution?
Like you said, for as long as there is access to those keys, the possibility the coins will be used is a real one.
I tend to believe in the same too (that the keys are irretrievably lost). It's the only explanation for why that clown would dare make those claims.