I guess that settles it. People will dump Slack and Discord on mass and move to the amazing IRC clients like LimeChat which are so much more efficient. it's well known that the number one thing people look at when choosing software is how efficient they are. Nobody cares about looks or features, just about CPU cycles.
No, what people care about are primarily network effects. They'll use whatever someone in the company decided to use (frequently Slack because it’s always been Slack since someone back in 2013 decided it was the hip choice, before it even had a desktop client), and they’ll put up with whatever dogshit client they’re served, because it’s out of their hands.
And what about Discord? It's almost exclusively used by people in their homes, there is no company pushing it down their throats.