IMO you are overestimating Romo's chances of getting to and winning the Super Bowl at this point in his career, having played in 4 games the past two years. Sure he has the experience factor that would give him a leg up on Prescott but he also has a track record of coming up short. I disagree that it is "plain and simple", in your words, that Romo gives them the best chance. He might, but to say it is plain and simple is essentially stating it as fact, which it is not?
I think letting the chips fall with Dak is the right play. If he fails in the playoffs then next year when Romo is no longer on the team you have a QB in Prescott who led his team to the playoffs as a rookie and who will have gained some playoff experience. If you stick Romo back in there and he does anything but win the Super Bowl then you are left with nothing more than "Well, once again a Romo-led team failed to get it done" and a franchise and fanbase—and possibly a significant portion of the team—left wondering "What if they just let it ride with Dak?". Obviously if Romo never gets a chance there will be the "What if they would have put Romo in there?" narrative, but we have had 10 years of Romo and nothing of significance to show for it.
As you said, glad it is not my decision because short of the Cowboys winning the Super Bowl whatever decision the organization makes is going to be second-guessed and heavily scrutinized.