They almost always play games against one another (SEC vs B1G) or they play nobodies (SEC vs Bowling Green, etc..) leaving no meaningful way to determine that team or conferences real value. The handful of games played between real opponents outside their circle of incest were often very close (Oregon vs BSU, Oklahoma vs Houston, etc...). Sure, a two loss SEC team probably does deserve a playoff bid if the SEC is as good as some think it is. We just don't know though.
Bowl season is going to be our best chance to see their real value. There will inevitably be matchups between them and the Big 12, ACC, or BSU in the playoffs that may expose them. Perhaps they'll blow some teams out and prove their value. Perhaps they'll get punched in the mouth. Gonna be telling when that time comes.