I don't buy this desperate idiocy that the message on the cake is thought of by anyone as some expression of the baker.
Well, the Supreme Court disagrees with you, as do I.
Not the first time a tiny few people have been wrong about something.
Is the sign painter also considered the author?
Absurd!
If a sign painter did not want to write the words "Death to Niggers" on a sign, he ought have the right to refuse to do so.
I'm sorry you don't think so and that you would prefer the State bully and compel him into doing so.