It was policy. Then that policy was loosened. The loosening is rather vague and still leaves a lot of room for trouble, so it remains to be seen just what the practical effects are. Now they "will be allowed to board U.S. bound aircraft and will be assessed for exceptions at arrival ports of entry."

I totally agree that focusing on the list itself is silly. It's a good example of why Trump should have divested his business interests prior to taking office, to avoid this kind of questioning of his motives. But it certainly doesn't look like these countries were chosen in any way based on his business holdings.