"I feel fear about an impending doom. Yudkowsky's argument that a superintelligent AI will inevitably destroy humanity seems to have no flaw. Yet, nobody seriously tries to sandbox AIs because they are too useful with access." No one takes Yudowsky's claims that AI will destroy humanity seriously. There are many people who are seriously trying to sandbox AIs.
But the handful of tech billionaires at the helm of the world economy absolutely do believe it. Or at least pretend to believe it. Or maybe they can't even tell the difference anymore as they strip-mine science fiction for any vision of a future that doesn't just look like an incrementally worse version of the present.