Well, that's a pretty silly statement. Saying it's impossible for this technology to be useful or a good thing, is just silly as if someone else said it's inevitable that it'll be a good thing.

The chicken pox vaccine didn't solve war in the middle east, but I'd still argue that it's clearly good that it happened. Same for AI; it can be good without needing to clear this insanely high bar you seem to feel is necessary for it to prove its usefulness.

For what it's worth, though, the part I'll agree with you on is that people will misuse the technology in ways to scam others out of money, or to make the world a worse place, maybe so much so that it eclipses any good that comes out of it. I'm just saying that's a choice they're making, not something inherent in the technology itself.