In the annals of hype about things that don’t yet exist, the metaverse has enjoyed an impressive rocketlike trajectory. Other tech giants, including Microsoft and Nvidia, are also pivoting to the metaverse. In the mid-20th century, “metaverse” was an obscure synonym for metapoetry, or poetry about poetry. Mr. Stephenson’s readers have wanted to go to the metaverse ever since. John Carmack, the lead developer of the first-person-shooter game “Doom,” once said it was a moral imperative to build the metaverse.

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