Henry Williams wasn’t always a believer in the Sasquatch. Growing up, he had of course heard the tales of old — of a legendary hairy, bipedal primate said to roam the forests at sundown.

The latest entry in the brand-name genre is Jerry Seinfeld’s Netflix movie “Unfrosted,” an astonishingly unfunny, deeply weird, live-action cartoon that is so clear-the-room dreadful it ...