We have a world culture, to have that there cannot be a culture which has not contributed
We do not have a world culture.
Most of our movies that we watch come from America, or have been produced in the Hollywood system, and been made outside of America. Most movie stars are american, or now live in the American system, which makes them somewhat americanised. Much of the television shows we watch come from America, most of the books we read come from america.
Sure, we can come up with a couple of good examples outside of the American media production systems, but the world culture is predominantly American, as there are far more numerous examples of American media.
If your statement is true, we should also have other countries contribute to this, and their contributions should in proportion to their population. Therefore, a sixth of all the media we see should be Chinese, and another sixth should be Indian. After all, those countries have a billion residents apiece, when the world population is six billion. We should see as much Russian media as American, as they are roughly the same size in terms of population, and American media should only be one twentieth of the world's media, considering it has a population of approximately three hundred million.
As it is, the major contributor is America, which is predominantly Christian, other contributors to the world culture are predominantly Christian, and therefore our most recogniseable personalities must be Christian.
As it is, I can instantly say, without any research, at least four out of the seven mentioned in the opening question are American. I do not know who Vera Wang or Paul Allen are, but I have a suspicion that the second is American. I know for certain that only one of them is not American - Bono is Irish.
Whether there are Muslims that should be included in this due to their political ideas, contributions to the arts and charity and so forth, is a matter of debate of a separate thread - it is not worth debating within the confines of this religiously biased thread.