“Don’t be such a dreamer,” says Bob (Esai Morales) to his younger brother, to which soon-to-be teen star Ritchie Valens (Lou Diamond Phillips), né Richard Valenzuela, quickly retorts, “My dreams are pure rock ‘n’ roll.” It’s the kind of blunt, overearnest exchange found in countless music-based biopics, but it also exemplifies La Bamba’s penchant for the cartoonishly archetypal. Indeed, everyone surrounding Ritchie is stripped of both nuance and agency as their roles in the film rarely extend beyond fueling or antagonizing the future icon.

Ritchie’s girlfriend, Donna (Danielle von Zerneck), the namesake of one of his biggest hits, is little more than a poodle skirt and a cheery smile, while his doting mother, Connie (Rosanna DeSoto), is the quintessential ultra-supportive parent. Bob is certainly the most fully fleshed out of this trio, but even most of his personal ups and downs are presented as being directly...