The difference between Tony and just about every other color commentary guy is that Romo is up to date on current NFL offensive and defensive schemes.
Most color guys quit playing the game over a decade ago. They still know a lot, but much of it isn't current. AFTER a play is over, they can explain in basic terms what happened.
They don't study hours of film of both teams leading up to coverage of the broadcast. It's obvious Tony does. He knows what's going on down there so well he can make accurate predictions.
Guys like Moose Johnson, Troy Aikman, Randy Cross, etc., they only have a casual observers view of the present game. Tony can tell you what keys a defender looks for to anticipate the coming play. The other guys simply don't have this level of knowledge. They might be aware of and can discuss general trends, but not in depth specifics.