As a long-time Wikipedian, I've occasionally had to deal with (understandable) ignorance about our policy on spoilers. I recall an edit war over the article on one of my favorite shows, Apple TV+'s Severance, regarding details about two of the main characters that were definitely spoilers, but also definitely fine to include per Wikipedia's current guidelines. I learned quickly to avoid reading Wikipedia articles before watching a show or movie to avoid getting spoiled.

Regarding trailers, I've recently started avoiding them for upcoming seasons of shows I watch, including Severance which is finally coming out with a new season in January after three years of waiting. Though I'll believe it when I see it at this point...