It might be more appropriate to pitch your question to the person who originally authored that claim. I was only going along with the premise in order to fashion my response.

Over a span of several years, I have used several Alternative Platforms, and have witnessed anger and outrage exchanged on each one; at least on occasion.

But I think it's generally accepted that Twitter (Mark-1), and Facebook, were probably set-up to facilitate a hyped-up atmosphere which then enticed many to over-indulge with their emotional responses.

Personally, I don't know of any platform that was set-up -- BY DESIGN -- "to amplify anger and outrage", because that would surely risk inviting bedlam and too much disruption.

But it would be reasonable to argue that the basic social-media model of clicks, likes, and follows was always going to entice those who prefer to engage in debate while dressed like a Gladiator.

As you asked a specific question about something that's clearly important to you; then why don't you now tell me what platform you believe has done more to foster online controversy?