The men who wrote the Constitution also didn't envisage an air force, what was the meaning of full faith and credit, due process, unreasonable search and seizure, equal protection of the laws, and about 37 other normatively ambiguous terms that permeate the document.
What you offer as agrument is what the law calls --ipse dixit--that's a phrase that means: "It is so because I say it is so, not because there is any legal authority, doctrine or common sense to my assertion."
And your argument is "I like porn, I want porn, therefore porn shall be called free speech because I say so. And it has to be available everywhere so I don't have to take any trouble to find it. And if communities don't want it, too effing bad. My wants come before anything else, and I call this - freedom."
Free speech refers to expression of ideas, not obscenity. The ACLU and pornographers are the ones who got the leftist Nazgul SCOTUS to shove porn down everyones' throats, whether they want it in their neighborhood or not.