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.

Threats of violence

Trade secrets

Walmart Takes Flight With Drone Delivery Expansion to Five New Cities, Redefining Fast, Flexible Retail - Walmart

No freedom is absolute.

Freedom of speech does not apply to:

Insider trading

Ozempic has ‘very rare’ sight loss side effect, EU drugs regulator finds - politico.eu

Perjury

False advertising

Revenge porn

What can I do after 18 cops raided my home, without a warrant, seeking a person who didn't live there and wasn't there, and also went through all of my stuff? The person wasn't on the lease, and they didn't see him enter.

Fraud

HIPAA violations

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.

Shohei Ohtani pitches sharp first inning for Dodgers before driving in 5 runs at the plate - AP News

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.

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.

Child pornography

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Conspiracy

Terroristic threats

Revealing classified information

What is the word for truth and its meaning in Koine Greek?

And much, much more.

Insurrection