$46 million opening is actually really good for a comedy (highest in years, and highest of any of the major’s participants careers). Problem is Sony spent way too much making it. It’s amazing how often movie studios fail in scope control. Uncontrolled costs make a hit (which within normal comedy revenue is where Ghostbusters landed) into a bomb.
Usually comedies are cheap but this one required blockbuster type levels of [bad] CGI.