I also suspect they rolled holdings from smaller speculative bubbles into this one. Auto driving, metaverse, etc. Those were big enough bubbles, they should've hurt some of these companies for a couple of years... And they didn't because they just keep rolling these holdings into the next bubble.
Don’t forget NFTs! (Hard to do as they are pretty forgettable). They propped up the nvidia/crypto bubble for a while after crypto went stale and then AI magically appeared just as interest in NFTs fell off a cliff, which was definitely a coincidence and nothing to do with the nvidia stock bubble.