It's because they're lying.
I'm sure you know that the words that come out of their mouth are worthless because of actions like this but for some reason, millions of people politely accept it.
They're never going to admit out loud "We just use freedom of speech to shame people out of deplatforming far-right extremists, we don't actually believe in it" or "We know the second amendment will never be used to overthrow a tyrant and we fully intend to be tyrants. We support it because it brings in $16 million a year in bribes and gains us millions of supporters who will tolerate literally anything except domestic abusers not having guns".
Every abuser has an excuse and it's never "I just really enjoy abusing people".
They also may have run the numbers and decided that social media teaches more kids to accept people regardless of race, gender, sexuality or neurotypicality than it trains to be far-right xenophobic dogshit.
I can't really think of any other reason they'd do this. They don't do anything unless it's in their self interest.