It seems unlikely. The Cowboys coaching was good this season considering the talent issues on defense.
Carr - Limited range. If they had a true #1 CB, then they could give him help, but Carr was the #1 most of the season.
Claiborne - Rusty and/or physically limited after long layoff due to injury.
Scandrick - Limited this season due to coming back from severe injury.
Brown - Rookie. Normally would get a lot of help, but the FS was also trying to help cover up for limitations at the other CB position, SS and MLB.
Church - Very limited range. FS can't cover up for everybody.
Hitchens - Good against the run but limited in coverage.
Durant - Player near the end with limitations.
Jones - First year as full time FS but also moved around to cover TEs. Tried to cover for other players but there were just too many and he couldn't cover up for all of them.
DL
Mayowa - OK as backup, but was the staring RDE.
DLaw - Injured and played RDE, but his best position is LDE.
T.Crawford - Probably better at DT but played LDE.
Irving - Good, but not able to focus on just one position.
Collins - Good but just a rookie.
T.McClain- Good but faded after minor injuries late in the season.
Thornton - Good as a backup.
J.Crawford - Try hard guy without much talent.
They had a lot of talent deficiencies. You can cover up for a back 7 player with limited range, but you can't cover up for 3 or 4 of them, especially when you're trying to use young players to do the covering up. You definitely can't do it when you don't have a quality pass rush. On DL they had players that were not in their ideal positions. The defensive coaches has a lot of limitations to scheme around. The good news is that just by adding a couple of better players, the surround players will get better. Carr would be OK if they had a SS with range and a better coverage LB next to Lee. All the DEs would be better if they had a true starting caliber RDE because it would allow the others to play their ideal positions..
Normally, an offense with at rookie QB and rookie RB would only win 13 games if they entire offense was covered up by a great defense. Instead, the Cowboys offense carried the load. It's surprising that a rookie QB had so much success considering that the receivers have limitations. Witten now has very limited speed. Beasley is good but scheme limited due to size. TWill is a good route runner but average at best hands. Dez is very limited as a route runner and still appears to have a very limited knowledge of the scheme. That's a lot of limitations when all added together.