Just look at the conditions in any society without free speech and you'll find your answer.
More abstractly, free speech is required for free thought. Without free thought, we're all thought prisoners to whomever controls the information we received. Musk's contention with Twitter is that they have been positioning themselves as that entity.
I'm not aware of that term being propogandist. Maybe I heard it somewhere, definitely possible. Do you object to the image? It seems perfectly fitting which is why I used the word.
I agree.