From my understanding of con law thus far, the 14th Amendment only applies to state actors. Therefore, since business owners are private actors, they shouldn’t be able to be sued for refusal to comply with same sex marriage.
Only the 13th Amendment applies to private actors, so unless the courts are arguing that same sex marriage is a “shackle of slavery” then these lawsuits should be thrown out.
Maybe someone further along in their law career can weigh in on the matter.
The problem is laws are being written at the state level that protect “sexual orientation” and increasingly “gender identity”.
I am slightly further along so I will assist. Look into the 14th Amendment’s Substantive Due Process Clause. During the Lochner era the Court agreed with you finding the clause covered economic liberty rights and found that private actors could not be subject to governmental regulation in that sphere. But after Lochner, the Court applied the same theory to Individual Rights (see Griswold, Roe, Brown). Now look at the Commerce Clause and its application and what you find is a shift wherein the Court found governmental regulation of private actors constitutional on the basis that there is a compelling state interest to protect citizens’ 14th Am Substantive Due Process rights. There you see the line of cases dealing with public accomodation. So a motel (Heart of Atlanta) cannot discriminate on the basis of any suspect class.
And that is today’s moment of Con Law.
Religious arguments were ruled useless with the passage of the original Civil Rights Act. This was predictable, and was predicted.