If freedom of speech is absolute, how come it's not applied for private spaces and for the Internet?

That’s what it is. You have no right to use other people’s stuff. If people let you use their stuff, they can tell you how you can use it, and they can tell you to stop using it any time they want.

HIPAA violations

You have freedom of speech. If I loan you my computer, I can tell you not to use it for certain things, because it’s mine, you have no right to use it, and if I give you permission to use it I can tell you what you can and can’t do with it.

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Revenge porn

No freedom is absolute.

Terroristic threats

Why do I want to be caught sucking dick by my wife?

Conspiracy

Insider trading

False advertising

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Perjury

If you’re wondering why free speech doesn’t apply to the internet, it’s because you have no right to use other people’s stuff for free.

Trade secrets

My boyfriend wants to break up over too many petty arguments. To me, they are molehills because I truly love him & don't really think twice about them. If he loved me would he work through it?

And much, much more.

Freedom of speech does not apply to:

Insurrection

I have wasted my 6 years for preparing for a government exam but did not succeed. Now I am 28 years old. What should I do?

Threats of violence

Child pornography

Revealing classified information

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Fraud

You have freedom to travel. If I loan you my car, I can tell you not to take it out of town, because it’s mine, you have no right to use it, and if I give you permission to use it I can tell you what you can and can’t do with it.