Most investors I've heard talk about the AI bubble have mentioned exactly that they know it is a bubble. They are just playing the game, because there is money to be made before that bubble bursts. And additionally, there is real value in these companies.

I would assume the majority of investors in AI are playing a game of estimating how much more these AI valuations can run before crashing, and whether that crash will matter in the long-run if the growth of these companies lives up to their estimates.