Why did they get rid of Tyrese?

Hey, I'm watching TWD for the first time and I know that characters will just die, but Tyrese's death was the first death that was kinda like, WTF, that was useless. He just gets snuck up on in a house by 1 walker and it didn't serve anything. The whole episode was just a filler episode tbh. Like was there a reason Tyrese got written out of the show in such a random matter? I kind of understand what the writer's were going for. Tyrese was arguably the last survivor of the group who still had that "good guy" mentality and they really emphasized that with his hallucinations, but at least let the man die in a more climatic way.