I really dislike multi-man matches at WrestleMania. But the WrestleMania bonus is the biggest payday of the year, so they try to get everyone on the card every year.
In a way, the card suffers as a result.
I think Harper is a really good talent, actually. Rowan I can take or leave. The Bludgeon Brothers, as a gimmick, may not be Mania-worthy, but I do think that as individuals both Harper and Rowan do deserve a Mania spot, other than the battle royal.