Well, if anything I would really split the credit though, Spielberg is a great director, but would have Indiana Jones or War of the Worlds would have been just as good without the starpower of Harrison Ford or Tom Cruise? Probably not. Could those movies have been just as good with the actors involved, but with a shitty director like Uwe Boll instead? I really don't think so. So yeah great actors + great director = great movie, unfortunately that's not always the case either.