> Something similar seems to be happening with "thinking" and "intelligence". Somehow these things had become ends-in-themselves

It's been that way for a long time. At least since Descartes "Cogito, ergo sum". But even the Greeks were heading that way almost a couple thousand years earlier.

> separate from the regular act of living.

How is thinking separate from the regular act of living for human beings? Our species is known as homo sapiens - the knowing or thinking human.

> I was born into had collectively come to think of the mind as the supreme good, and intelligence as the greatest virtue.

I guess it comes down to what you think the answer to the basic question posed in the catechism is: "What is the chief end of man?" This is going to be the crucial question for us as a species in the age of abundant AI. Or as Wendell Berry posed it: "What are humans for?"

> But this is, in some way, in contradiction the basic fact of existence and mortality: no amount of cleverness can circumvent death, and all the glory attainable by feats of the intellect are only futile vanities compared to the privilege of being alive itself.

But being alive for us humans entails a lot of thinking. Is the unexamined life worth living?

what will it mean to be human, homo sapiens, in a world where the thinking is done for us?