In the NFL during the Shula era, being a strict disciplinarian worked but other than Belichick, the successful coaches today don’t seem to be that type of coach anymore.It looked better the next day. Having said that it has always scared me when they brag about a coach being a "players coach". All the greats were very strict, and didn't spend a lot of time worrying about who did or didn't like him. When things get dicey (and make no mistake they will) a coach that demands respect can much easier step in as a leader and those around him will follow, as opposed to your "bro" trying to suddenly step in and expect everyone to suddenly just start walking the line. There MUST be a hierarchy, and everyone must know their role and how to stay in their lane.
I don’t see Andy Reid, Pete Carroll, Sean Mcvay, or Kyle Shanahan being a head coach that is considered strict disciplinarians. They are viewed as great teachers who also have good relationships with their players.
The reason I feel the coaches who have left the Patriots to become head coaches haven’t had success is they have tried to bring the Belichick disciplinarian way to their job and players today just don’t buy into it unless you have Belichick’s history of success.
The players today have a much different attitude toward disciplinarian type coaches than they did years ago and while it is important that the players respect the head coach, I think being viewed as a players coach is far more important today than it might have been during the Shula era.