Hollywood executives stared at the weekend numbers and blinked twice. Backrooms opened to $81.5 million domestically. Obsession added another $26.4 million in its third frame. And Star Wars: The Mandalorian and Grogu slipped to third with $25 million after a brutal 69 percent drop. Two films made by creators in their early twenties. One with a $10 million budget. The other produced for less than $1 million. Both now sit ahead of a Disney tentpole whose reported costs, including marketing, reportedly approached $300 million. The math does not lie. The implications stretch far beyond one Memorial Day frame. Kane Parsons directed Backrooms for A24. The 20-year-old had already built a massive following through his YouTube series based on the viral creepypasta concept of endless, liminal office rooms that trap the unwary.…