The linked article references many such cases, although I don't think they went to the Supreme Court. The fact that these cases didn't go to the supreme court, if anything, indicates that these laws were clearly unconstitutional and therefore didn't need to go that far.

Anyways, the supreme court has addressed freedom of speech laws as relates to billboards, such as this example last year. That case is not relevant to this case, ofc, since this bakery sign is not digital. Also, I'm not a constituional lawyer. I'm just asking questions about this because I'm genuinely curious.