I just want to say, I’ve enjoyed reading this thread. Love the level of discourse that happens here, it’s quite unlike most corners of the inter webs, felt my mind changing back and forth several times as I read. By the end here’s what I personally have come to:
The law forcing anyone to express a sentiment they disagree with is compelled speech, and therefore wrong.
However the law should punish refusing to provide any regular service (any that does not express a viewpoint directly) based on the expressed or perceived beliefs (or protected characteristic) of another person.
I do think it gets muddy when the “service” is access to an otherwise private space which will be used by the client to express some opinion publicly. If a e.g. venue/billboard renter does not agree with Clients’ opinions or the views that will be expressed, is she being compelled to “speak” by Providing that platform like the cake baker?
I feel of two minds. On the one hand, I think it’s not the same, and the law should punish failure to rent to any paying (and rules following) customer, because the service is rental of a space to someone. No one is forcing the renter to directly express agreement (in fact she could stand in front and hand out pamphlets about how awful her customers’ views are if she wants to). Unlike the cake, she’s not being asked to say or do anything.
But then it is a private space/billboard owned by the renter - so should they not have complete discretion to whom it is available, even if outright discriminatory? In addition in the case of a billboard at least the renter is having to at least publicize a message they might not agree with. So it could be thought of as compelled speech. And this maybe could be stretched to renting a physical space where speech will be heard as well.
And hence the platforming/no platforming debate. I tend to say let everything be heard, just make sure anyone who wants to can argue back. But I can understand the view that people shouldn’t be forced by the law to pass along messages they don’t agree on as this is at least close to compelled speech.