This is the problem with fans, they have to go to extremes. It's either Romo is one of the greats or Romo is one of the average. There's no middle ground, which is where he belongs.
Romo was good enough to win a Super Bowl with if the rest of the elements had come together at the right time, but we never had a great defense when Romo was playing well, or we were rebuilding the offensive line when the defense was actually decent. It takes more than just a quarterback to win a Super Bowl or even win in the playoffs.
Because Romo's teams did not experience Super Bowl success, he will fall short of the Hall of Fame. Personally, I believe in the right circumstances, he would be considered equal to Brees, who I don't consider an all-time great but great at times and in the right situation. Put it this way: NO has had five seasons at 8-8 or below with Brees at QB and in five of the six years the Saints have made the playoffs, they lost their only game. If not for a magical 2009 season, there wouldn't be much of anything to separate Brees from Romo (and the reason for that magical season had as much to do with the Saints' defense being great at forcing turnovers as it did with Brees).