This ruling was not based on religion.
Basically, if your job involves messaging, then you can refuse to produce messages you don't agree with. It doesn't necessarily have to do with religion.
For example, suppose a Russian hired you to make a pro-Putin website. You can refuse, even if there is a state law barring discrimination by national origin.
This only applies to messaging. If the same Russian wanted to eat at your restaurant or stay in your hotel, you cannot refuse on the basis of his ethnicity.
There are plenty of recent examples of the SCOTUS inappropriately making up new religious rights. But this is not one of them. The court even pointed out that their decision could be used against religious expression.
For example, if a Christian asked an atheist to design a "He gets us" ad, then previously the atheist might have violated the law if he refused (since religion is a protected class). According to the new SCOTUS ruling, the atheist cannot be punished for refusing.