When you have the ability to deplatform, censor, or shadowban someone in any way shape or form, you don't actually have to engage in the discussion. You're bigger than them: you can just shut them up and save yourself the headache.
Will you win in the short term? Of course, because the idea is still there all you did was sweep it under the rug.
When you don't have any of these tools at your disposal, all of those ideas come out of the rug and your only choice is to engage in discussion and speak rhetorically. You are forced to learn to be persuasive, forced to learn to make a logical argument, and forced to understand the other person's perspective in order to refute it.
This dichotomy is a causal link. If you're in a part of the internet and no real discussion is happening, it's because someone has power over the other.