I'm old enough to have heard this before, once or thrice.

It's always different this time.

More seriously: there are decent arguments that say that LLMs have an upper bound of usefulness and that we're not necessarily closer to transcending that with a different AI technology than we were 10 or 30 years ago.

The LLMs we have, even if they are approaching an upper bound, are a big deal. They're very interesting and have lots of applications. These applications might be net-negative or net-positive, it will probably vary by circumstance. But they might not become what you're extrapolating them into.