People were very into his feud with AJ last year. We wanted to see AJ win. It's the same thing that happens whenever someone gets into a feud with Cena. It's coincidentally somehow nearly always guys anyone who hates Cena would love, battling an obstacle they talk about few overcoming. Weird!
No one said it's smart booking, which is why it's all the funnier it's so hard for some to understand. Like people think they're immune to works now, but they'll still believe the legends about how much Andre drank or how otherworldly strong he was.
You have people like Cena, Reigns, Triple H, Owens, Austin, etc all talking about how the mixed reactions are part of the work, explicitly telling you how wrestling is working, and everyone's like "nah, you just suck at making wrestling good. But I still watch and talk about you all the time."