Yeah, an undrafted FA having one of the most respected NFL head coaches in many years sign him and keep him over two drafted QBs despite being injured more than he's been healthy certainly says he's no good. Especially since he's a terrifyingly old 23 years at a position where the average age of a starter is 28.
Aaron Rodgers sat for 4 years behind Favre, Kaepernick wasn't good enough to start, Kurt Warner wasn't good enough to beat Trent Green.
I'm in no way saying Bray will be as good as any of those guys were or have been, but he's certainly got enough people who think he can be a starter some day or he wouldn't still be with the Chiefs on the non injured list. And most who know football will certainly agree his ceiling is higher than the current starter in Kansas City. Whether it happens or not is up to his coaches and his health.