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

Revealing classified information

Inside Ukraine’s audacious drone attack on Russian air bases - CNN

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

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.

Giants Activate Jerar Encarnacion - MLB Trade Rumors

Perjury

Insider trading

Terroristic threats

Biotech pauses trial after second patient death linked to gene therapy - The Washington Post

And much, much more.

Insurrection

Freedom of speech does not apply to:

Why are perceived or real slights interpreted as rejections and reality by pwBPD?

Threats of violence

Trade secrets

Revenge porn

How do you dry your hair fast?

Fraud

False advertising

No freedom is absolute.

Compare Chatgpt vs Claude AI

Conspiracy

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.