Since Trailers Like To Be Misleading...
Since trailers like to be misleading nowadays, I'm starting to think that's not Michael in the closet at the end of the trailer. I've seen the trailer a bunch of times because I watched a ton of reaction videos, mainly to see what everyone thought of it and how many will actually be going to see the movie. So every time I see the whole closet scene at the end, I'm becoming more and more convinced that it's not Michael standing in the closet. My guess is that the person in the closet is the girl's boyfriend messing with her/(Halloween) pranking her. That's IF she has a boyfriend. But we see her walking with a guy earlier in the trailer (along with Laurie's granddaughter). So my guess is that it's him in the closet and dressed as Michael. Plus Michael really wouldn't be standing there like that. He'd probably stab her immediately when she opened the door to see why it wouldn't shut or before she even fully openthe door so the audience can see what's in the closet. (Maybe a massive jumpscare since everyone is expecting to see a continuation of what we see in the trailer.)
They could have a different cut/take for the actual movie. Maybe he stabs her right away or slits her throat. Michael seems to like slitting throats.
But something seems off about the whole thing. And trailers like to be misleading nowadays, especially horror movies (also Marvel). So I'm going with that it's not really Michael standing in the closet. Her boyfriend or someone is pranking her or something. If she is going to die, I don't think it's going to be in that scene.