Jerry has owned the team 35 years. When he started, he hired a great HC who had in it his contract to control player personnel and have complete control of the team. After Jimmy left in early 1994, Jerry seized full control and has never allowed a head coach since to have that level of control.
In his first 5 years as owner, Jerry was so busy getting the business end of things done, Jimmy was the one putting together the personnel moves that led this team to winning 3 SBs in 4 years. (Jimmy was here for only two of those SB wins but it was his players and his roster development that led to those SBs)
Put it another way. in the Jerry era, this team won 11 playoff games in 6 years. In the following 28 years, we have won 4 playoff games. It’s pretty obvious Jerry Jones does not know how to build a championship level roster without major help. And he doesn’t like getting help or admitting mistakes. Thus we have the last 28 seasons and counting.