It's not about "back on the plantation"
It's about what people will try and do with this new ruling.
Essentially accommodation laws are now BELOW a person's religion.
Who gets to decide what a person's religion is?
Clear Christians can now use their religion to official be anti-gay. They can refuse to serve gay people.
"But, she asserts, the First Amendment’s Free Speech Clause protects her from being compelled to speak what she does not believe. The Constitution, she insists, protects her right to differ." (page 2)
This case is using the First Amendment, saying that if someone has to say something they do not wish to say, it goes against their right to free speech. Essentially she'd be writing the website and doesn't want to write things like "they fuck up the bum four times a day" because.... I mean, who are we kidding here, there's NOTHING she'd have to write on her website that wouldn't be the same as writing for a straight couple.
She doesn't need to "believe" marriage is between a man and a woman to write something like this.
However, imagine a black man walks into a restaurant. The restaurant says to call men "sir" and women "ma'am" and the server says "my free speech says I don't have to call any [insert N word] "sir", I'm protected from this.
Or even further "I don't have to speak to black people at all", imagine a restaurant where a black family walk in, and the restaurant refuses to speak to them.
Literally, we're talking segregation here, and I bet you'll find a whole load of fucking bigots using this case to get around a whole load of shit here.