This is a completely unfair and unfactual assumption you made.

I entered Saudi Arabia just this morning with a star of David necklace on my neck (yes it was under my shirt, but it wasn't hidden or anything). There was not even the slightest sign of discomfort nor disapproval. Just a friendly and helpful border officer who said, "Welcome to Kingdom. Have a wonderful time".

And this notion of separation into "undesirables" in Gulf countries is also just plain false. The UAE just granted visa-free access to Indian nationals.

I would check the information you are relying on if this is the kind of assumptions you are making.