I pretty much already stated all that. When it's about performing some act, and where "what you don't agree with" impacts the work being performed.

...so if we go with the previous example, a photographer should be allowed to deny service to an interracial couple if they're "not at ease" with seeing them -

"move a little closer", "look this way", "kiss lightly ", etc., etc.

Well the hypothetical protection you're describing would in practice protect and embolden people who hold white supremacist beliefs. I say "embolden" because you know what a racist photographer would do without those protections? They'd either turn them down, or they would take the pictures, take the money, and keep their ugly mouths shut. Because those are better options than fighting a battle they believe they could lose.

However, if they are legally protected by the federal government in communicating to interracial couples they won't provide service to them because they are an interracial couple, can you imagine the actions a now unrepressed fanatic would take? You think you wouldn't see "whites only" on some of these people's websites? And can you begin to imagine the fear and anxiety that would inspire in the people who now have to see those kinds of notices while looking for a wedding photographer? A wedding cake? Who now have to ask every photographer and cake maker if they serve "couples like them" if they don't have a notice? Can you see the parallels?

Legal action that empowers bigots and disempowers those they hate at scale is all it takes to develop a foundation and vocal support for the return of socially acceptable and legally backed discrimination. And you better believe that a foundation is exactly what the far-right politicians that brought about these "protections" view it as, because plenty have signaled openly that they have no interest in stopping legalized queer discrimination here, and will absolutely use this decision to justify going further in the future, the same strategy they use for all their culture wars.