In talks and papers I often describe AI as a "rational bubble", a finance term describing asset valuations and investment being increasingly disconnected from cash flows, despite all actors being rational, not merely bananas.

There is a good new Chicago Fed paper laying and sythesizing the latest work on the topic, and it's a helpful framework.

Why Bubbles Occur: Revisiting the Rationality Debate
https://www.chicagofed.org/publications/economic-perspectives/2025/3