Dak has by far had the superior teams and supporting cast around him bar a year or two. Romo picked up and made alot of average players look good. Many left Dallas to go on and do nothing else. He also practically ran his own offense per ex teammates. He got tons of hate for his picks at the end of the game however it's going to happen when you carry trash defenses for the majority of your career.
Romo had what 23 or 24 comeback victories between 2006 - 2015 leading the nfl. Lead ALL quarterbacks in the 4th quarter and overtime passer rating during that span. His cowboys defense from 2010 on gave up more 30+ games besides two other teams. He gets hate with late game INT however when your defense constantly let's the opponent score at will of course INT will happen. Let's not forget quarterbacks such as Brady, Rivers and etc had more game ending plays then Romo from 2011 on. Romo also had overall good postseason stats.
In the end its a team game. We should be grateful we lucked into two very talented quarterbacks who at the end of the day are good enough to win a superbowl. But if you had to pick Dak or Romo to build around from what we have seen from them you gotta lay off the drugs if you're going with Dak.
I truly hope Dak shows off this post season and for the rest of his career closing this debate. Dak is still young and learning.