The onrushing AI era was supposed to create boom times for great gadgets. Not long ago, analysts were predicting that Apple Intelligence would start a “supercycle” of smartphone upgrades, with tons of new AI features compelling people to buy them. Amazon and Google and others were explaining how their ecosystems of devices would make computing seamless, natural, and personal. Startups were flooding the market with ChatGPT-powered gadgets, so you’d never be out of touch. AI was going to…