Some would conclude atheists are out to offend believers.
This is sophistry. Courts don’t get that philosophical. Their test is something like:
1. Does the material start from a question and proceeds by some logical process to offer an answer? If so, this is protected speech.
2. Does the material offend the feelings normally present in a group of people likely to access it? If so, this speech is suspect.
3. Does the suspect material appeal primarily to feelings or to reason? If the answer is feelings, the suspect material is not protected speech.
This does not mean the offensive material must be banned. It simply does not enjoy a free speech protection. The authority may ban or censor it if the society as a whole is better off without it, and torts can be brought by private parties against it.