Few counterpoints:
Most people, even toxic people, do have positive qualities.
At the most basic strategic level, it’s vital to recognize this so that we don’t fall for such people in the future. It’s sooooo easy to say “well so and so can’t be too toxic… I mean, they volunteer at the soup kitchen on weekends” or whatever. That’s part of how they (intentionally or unintentionally) lure you in. All very valuable for engineer-types, who may tend to be very literal in actions and their interpretations of others’ actions.
At a more nuanced strategic level, it’s good to recognize that since all people are a mix of positive and negative traits, How can we coexist with such people in cases when we can’t avoid it? It’s simplistic to say “just avoid toxic people” — it’s a good “north star” but is often impossible or impractical. e.g. it’s convenient to say “just cut toxic family members out of your life” and sometimes it’s the right call, but I’ve heard people toss that phrase around like it’s nothing and wow it’s heartbreakingly glib.
I think it’s also valuable for introspective purposes. It’s very easy to fall into the mindset of “well, I’m a good person because of X, Y, and Z” while blinding ourselves to negative ways in which we affect others.
Finally, yeah, sure — I admit it. I like a puzzle. Specifically the puzzle of figuring out if these people believe their own bullshit!
(For the record, I thought this movie was incredible, though HN’s collective “meh” on this thread was expected)