Aston’s Lagonda went full wedge and digital in the late ’70s, pairing a 5.3L V8 with a sci-fi dash. Unreliable and pricey, it still grabbed headlines and buyers—helping keep the company afloat.

In 1990, Italdesign’s Giorgetto Giugiaro unveiled Bugatti’s ID90 concept—an aerodynamic, Royale-inspired alternative vision ...