“Always Be My Maybe” feels a lot like a movie propped up by a stunt, a high-gloss romantic comedy so mired in triteness and unconvincing emotions that its main recommendation is the appealing diversity of its cast.

That stunt is a wonderfully self-deprecating appearance by Keanu Reeves, but we’ll get to him in a moment. The early scenes, set in San Francisco in the 1990s, have a charming ease as young Sasha (Miya Cech), a lonely only child, finds solace at the home of her friend and neighbor, Marcus (Emerson Min). The enticing Korean meals cooked by Marcus’s mother (Susan Park) are especially consoling, so it’s no surprise to find the adult Sasha (the dauntingly confident Ali Wong) swanning around Los Angeles as a glitzy celebrity chef.

One-pot comfort food, though, has been replaced by elaborate plates of Instagrammable art, which is how we know that Sasha has lost touch with her roots. The movie is rife with this kind of shorthand, sketching characters’ flaws and attributes in broad sitcom strokes: Sasha’s faithless and short-lived fiancé, a restaurateur who practices capoeira, gives Daniel Dae Kim little to play but an empty suit. Even so, he’s a more credible partner for Sasha than Marcus (a bashful Randall Park), who might look like an adult but hasn’t yet figured out how to behave like one.