Your critique is totally spot on. I can’t stomach Shyamalan’s current movies. Oddly though despite the cheap plot twist and how much it got made fun of in the media at the time, I love The Sixth Sense. I still watch it to this day. The scene where Cole sees the dead biker and tells his mom they’re standing outside the car window? Goosebumps every time.
I cant find the source right now but when Shyamalan wrote the Sixth Sense, it was a complete script on about the fifth draft before he even _thought_ of the twist. And I think thats why its such a great movie. Its like a twist that gives you a whole new movie on top of the perfectly good one you've already seen. And the twist is not just a gimmick, it has emotional depth.
edit: I first saw the sixth sense in perfect conditions - a pirated VCD from Malaysia before any publicity for it had happened in the UK, so had no idea what I was getting myself into other than it had Bruce Willis in it. Absolutely blew me away.
edit: found the source:
According to an interview in Scenario magazine (Volume 5, Number 4), Shyamalan had written five drafts of the screenplay before an idea came to him that transformed it into something totally new, leading to a landmark film with powerful performances from the film’s stars. It happened in the sixth draft.
https://www.stevendeeble.com/2016/05/31/evolution-of-a-scree...
I think you're right that The Sixth Sense is worth rewatching more so than his later ones.