I've seen some movies not knowing anything about them by avoiding trailer (this being much easier in the 1990s...) Movies seems to work better that way.
Though it can be jarring: Eg. Silence of the Lambs or Leaving Las Vegas.
I avoid trailers like the plague. When reading reviews I'll skip most of it. I want to know the gist of the plot, and I want to know the summary.
I enjoy movies so much more this way. Sure, sometimes I end up watching some duds, but most of the time I'm really engrossed and I love the surprises.
If I watch a trailer, especially the modern 5-minute condensed versions, I find it takes away >90% of the excitement. Doesn't matter if the movie comes out next year, the trailer will come back to me and I will recall the spoiled plot points.
Though it can be jarring: Eg. Silence of the Lambs or Leaving Las Vegas.
The Onion had a good take on it:
https://theonion.com/wildly-popular-iron-man-trailer-to-be-a...