The summaries are not always clear, but essentially the ruling says that as long as you have a policy that bans religious or political symbols generally, then that's fine, if such policy exists to present a neutral image.
However, what you can't do is ask an employee to remove their headscarf (or presumably another religious or political symbol) simply because a customer asks for it, which is what happened in one of the cases, without such a policy.
The existence of a general policy is the key.
