Nvidia was and still is overpriced. Yes, AI is now on the mainframe stage. Soon it will go to consumer devices with a billion of potential users and the training and the required hardware for it will be very different: much less power consumption, continuous training etc, just like our or animal brain. Consumers did buy computers for $1000 in 1990s. They may buy a robot for $10000 tomorrow. The benchmark for the market cap in this segment are car manufacturers or Intel in 1990s.