Hypothetically speaking, lets say Dallas gets your dream staff (HC, DC, OC, and ST coordinator). Rather it be Riley, Rivera, Rhule, Meyer, etc.
Do you really believe they can change this team within an offseason?
The new HC will have to bring a modern playbook and a new scheme. That is not easy in itself. After that, comes the players....
As we all know, the culture of the Cowboys is a major problem. A new HC may help with this, but it will not solve the problem completely, especially not in one offseason. Think about it. What is one thing our players lack? Leadership. Brotherhood. Wills to win. Compassion for the game. Thinking as a unit/team rather than an individual.
You look at the Ravens and you see a classic football team. A team that has each others backs (brotherhood). Everyone in that locker room gets along. Everyone in that locker room plays for the team rather than themselves. Everyone in that locker room has energy, passion, and most of all, they have fun at the end of the day. Even though all these players chase money, contracts, and likes on social media, they don't put it ahead of football.
Our players do NOT do this. Rather it be because Jason Garrett allows it, or the culture of Jerry Jones, it will not be an easy fix AT ALL. Look at Jaylon Smith or even Zeke this season. Shannon Sharpe made a good point on Undisputed Today when talking about Le'Veon Bell and his stupid bowling situations. He said "Players today don't care about winning. They could care less about winning. They care about social media and likes." That perfectly represents our team.
Not only does the new HC have to create a new playbook, gameplan, and scheme, along with changing the culture and attitudes of our players, they have to adjust to the team themselves. Settling into a new team is very hard, especially if we grab a college HC. On top of that, our players will have to adjust as well. Some players struggle more than others when it comes to change. That will be our team next year.
On top of THAT, we have like 20 or 30+ players to resign or let go of. That likely means we will likely have a lot more new players on our team through the draft, free agency, or trading. This team may look very different from what we see today (hopefully for the better).
New players, new HC, new scheme, new culture, new attitude, new gameplan, etc. 2021 may be our year, but along with our schedule (we play the NFCW (YIKES), the NFCN (Browns may improve, Steelers look good even with injuries, and the Ravens may still be redhot), possibly the Saints if we win our division, Packers or Vikes, and more, 2020 does not look like our season at all.
I would NOT raise my expectations beyond anything we feel right now for 2020 no matter what HC or player we pick up. If you do, you will be disappointed.