And let me segue into that movie because I think it kind of applies in this situation. PR was made by someone who's actually artistic, that loves the kaiju movies, someone who was willing to cast relative unknowns in the movie... and it didn't do that well domestically. Sure, word of mouth pushed it further...but again, I think the team around Ghost in the Shell is garbage. Again, this is a heartless cash grab.
Pacific Rim didn't do well in general because it's a horrendous movie with bad pacing, a weird story, a jarring tone, bad actors, unfortunate marketing, disappointing action and very dark visuals. I doubt a bankable star would've helped. I'm also not even sure if there are numbers that show whether there are really any bankable stars left (or if there ever were any).