Because what it actually means is the freedom for them to spew their hate speech without consequences. Freedom of their speech, not others’. They hate being “punished” for their hateful ideologies and view it as censorship. Being able to spread their hateful beliefs to large groups is extremely important in propagating it to other people. Conservative created platforms are inherently limited by the fact that their audience is not only quite small but also everyone there already believes their bullshit. They want and need to place their hate in mainstream places where others will see it and hopefully come to believe it
There’s also the bonus effect of reducing both the amount and proportion of non-conservative voices.