Seems like a weird case for the Supreme to have taken in the first place, I don't really see how it clarifies anything really, since we still compel businesses to not restrict services based on protected classes.
EDIT:
Feel like I'm being clumsy in my writing above. What I'm trying to argue is--to me--it seems the crux of the case is whether (a) "won't make sites for gay marriage" == (b) "won't serve gay people in my restaurant". The latter is pretty clearly illegal, even the ruling upholds that. So if you think (a) == (b), then the ruling seems contradictory. If you think (a) != (b), then the ruling makes sense, akin to saying "a heavy-metal focused website maker has every right to refuse to make country music websites".
I can see both sides of the argument (a) == (b) and (a) != (b). What I can't see is how the First Amendment can be used to justify whether (a) == (b) or not. If you _already assume_ (a) != (b), then you can say a business shouldn't be compelled to say anything. However, you must first justify that (a) != (b). I don't think this ruling does that, so I don't think it's a very useful ruling for anything in the future, even if I see the merits of preventing overreach in government censorship.