Yeah it was not for concept of free speech, it was counter culture movement using term free speech to their advantage as a political tool to get their message out, because they need it at the time. But free speech meant for them privileges without responsibility. That is why you aways hear word "F" for freedom and never "R" for responsibility on the left. Privileges imply obligation, duty. But that is not what the left is about. They kids at Berkley were not philosophers, arguing about it on the marketplace of ideas, they were fledgling revolutionaries demanding it by screeching about it like banchess as my friend like to say.

free thought, noun - thought unrestrained by deference to authority, tradition, or established belief, especially in matters of religion.

free speech, noun - the right of people to express their opinions publicly without governmental interference, subject to the laws against libel, incitement to violence or rebellion, etc.

“People demand freedom of speech as a compensation for the freedom of thought which they seldom use.”
― Søren Kierkegaard

“The problem with today’s world is that everyone believes they have the right to express their opinion AND have others listen to it. The correct statement of individual rights is that everyone has the right to an opinion, but crucially, that opinion can be roundly ignored and even made fun of, particularly if it is demonstrably nonsense!” ― Brian Cox

If you say things that are insane or stupid you should be able to express those thoughts in a civil discourse. And others should have the same freedom to criticize or disagree with you in civil discourse. If you only grant freedom of speech to one side you are censuring free speech and that is exactly what "political correctness" is design to do. it is a form of linguistics fascism.

BTW. Writing something on a piece of paper and carrying it around is not speech is heard mentality in writing.

“A liberal will defend to the death your right to agree with her. Disagree with her, and she will call the police.”
― Peter Hitchens, The Broken Compass: How Left and Right Lost Their Meaning

“The trouble with free speech is that it insists on living up to its name.”
― Jonathan Yardley

“Comrade, your statement is factually incorrect.”
“Yes, Dimitri, it is. But it is politically correct.”

“The point of Political Correctness is not and has never been merely about any of the items that it imposes, but about the imposition itself.

“Tacit collaboration by millions who bite their lip is even more essential than lip service by thousands of favor seekers. Hence, to stimulate at least passive cooperation, the party strives to give the impression that “everybody” is already on its side. ”

― Angelo Codevilla (The Rise of Political Correctness)

Recent developments show that the left is based on little more than the childlike dream of escaping the harsh realities of maintaining a civilization. They voted for the magic of black skin when supporting a junior senator with no meaningful life experience to be president. What they really hate about Trump is he pulled back the curtain and showed how superficial and pretentious the fantasy of 50 plus years of youth culture has been. We live in a world now not unlike that described in the "Lord of the Flies".