The way that fans react to roster changes is one of the ever-interesting aspects of professional sports. Some are met with glee and others with extreme derision. And then some, like the switch from Tony Romo to Dak Prescott, split fanbases right down the middle.
In 2017 and perhaps for many years to come, a large number of Cowboys fans will resent Prescott and judge him harshly as a result of Tony Romo's problematic exit. Even though all he did last year was go out and play well, Dak will carry the burden of being the guy who “forced Romo out” despite having no say in the matter.

A sample of this was already seen in last year's playoff game. Dak's slow start to the eventual loss against the Packers became a rallying point for bitter Romo fans. They asserted that Romo would not have let the team fall behind 21-3 and created such a deep hole to get out of.
Nevermind that Prescott finished the game with more yards (302) or touchdowns (3) than Romo's ever had in a playoff game. Nevermind that his 63.2% completions or 103.2 passer rating were both higher than Romo's career averages in the postseason.
Nevermind that Tony Romo had a 2-4 record in playoff games.
That is just a glimpse of the rocky terrain that Dak Prescott will have to walk next year, if not longer. His failures will be exacerbated by whatever lingering devotion to Romo, and bitterness over his departure, exists among a segment of Cowboys fans. Sometimes it will be logical, sometimes it won't.

Prescott is facing a unique situation compared to his predecessors. Don Meredith, Roger Staubach, and Troy Aikman all retired before Craig Morton, Danny White, and Quincy Carter got their turns. The closest comparison is Tony Romo himself, taking the starting job away from Drew Bledsoe midway through the 2006 season.
Bledsoe was not an iconic Cowboys QB, though, having just played one season prior to 2006. Fans were still waiting for a return to the glory days of the 90s and the young, exciting Romo quickly gave them hope of that. He got everyone looking anxiously towards the future.
The irony here is that Dak Prescott was better than 2006 Tony Romo in every conceivable way. He was more accurate, had better judgment, and was more dangerous running with the ball. This was in spite of being a rookie who didn't know he'd be starting until late August. Comparatively, Romo has been getting NFL coaching and practice for three-and-a-half seasons before becoming a starter.
Given that, you'd think the excitement for the Dak Prescott era would be even higher than what we saw with Tony Romo in 2006. But that shows you the power of Romo's legacy and the love fans had for him.
That love, now denied, will create a new challenge for Prescott in 2017 and perhaps years to come. He will be judged more harshly for having been the instrument of Tony Romo's demise, no matter how unfair that is. In the end, he may not win some fans over until he does what Romo never did by getting the Cowboys to NFC Championship Games and Super Bowls.