Because the left does not approve of hate speech, which is what right wingers immediately rush to spew whenever they see freeze peach.

People confuse free speech with freedom to harass and driving people out. When 90 % of a site (as an example) are antisemitic rants and antisemitic memes Jews are actively driven out of the place. You actually make a place less free by allowing discrimatory content. People have to potentially hide their identity or have to endure constant hostility. In consequence you are removing their voices from the platform.

I guess most "people on the left" would agree that you can create such a platform for yourself and your buddies but do not call it "free speech" when in reality it just creates a venting platform for a certain type of people.

I’m sure everybody on the left agree with the concept of free speech

Not sure if serious......?