Sure, but it's not like Lee and Tate's characters were smeared and totally dragged through the mud? If there's context I'm missing here I'd be glad to hear it. Most people aren't going to take it seriously at all so what's the problem?
A biopic, where you're straddling the line between educating the audience but also make a movie for entertainment, is different. Once Upon a Time in Hollywood, as many people have said, is basically a fairy tale.