Genuinely, if b4nny wanted to be the best player he could be and increase his chances of winning as much as possible – which he has a financial incentive to do so, as his branding is all about being the number 1 TF2 player, he would frame the criticism and problems that he has with his teammates with respect.
e.g. “I want you to do X Yight, because it’s the best for the team/I think it’s the best play/etc”, then listening to others perspective and working with his players to come to good resolution to the problems in game.
Everyone tilts and gets angry when they care in a video game and its understandable if you flame or rage at your teammates from time to time. But consistently putting people down and whinging about everything, is a sure-fire way to get people want to spend less time with you as you drag the mood down for everyone.
This isn’t tier 1 CS or League of Legends worlds; nothing is on the line for anybody but b4nny himself. Maybe I don’t have the full story or all the information, but this seems like paper thin mental from b4nny.