Megalopolis seems like a bit of an outlier here because of how much of a labor of love this was for Coppola personally. Most of the film's funding came from Coppola himself and I'm sure he used a few of his connections he'd made over 50+ years in Hollywood to get it produced, but I don't think anyone involved ever expected a narrative-heavy sci-fi(?) film to break any box office records in 2024.
As for the rest of the movies mentioned, I feel like it's a combination of A) too little incentive to see a movie in theaters and B) film budgets seem to be wayyy too high for the final product.