Just a few years ago, the alternative protein industry promised to revolutionize the way people eat burgers: They would still sizzle and bleed, they’d taste great, but they wouldn’t actually contain any meat. Today it seems that, if that revolution is still coming, its arrival has been more than a little delayed. Sales of plant-based meat and seafood have fallen over the last two years, and a recent bevy of headlines suggest that this latest wave of imitation meat was just that: a passing fad.