This is nothing new. And no different than the cake from the baker. You can't be forced to provide a service for another against your will.

It's discrimination on the part of a store owner if he doesn't sell you a pre built design from a storefront. It's discriminatory against the designer if you try to force him or her to design something for you against his will or beliefs.

Pretty straight forward. They can try this all they want but now they've got a ton of precedent. Good job.