Your arguments about Zidane are strange, the first one is directly linked to the fact that he has only managed for 2 and half seasons, no one can actually claim that he doesn't build teams or tell what he wants. The other two points are contradictory, he doesn't have a style but you then enumerates what he wants and doesn't want.
I have watched enough Madrid games in the league to know what I'm talking about. I followed them a lot in his era. I know very well why you'll defend him anyway but all honestly I'm not in the mood to get into a 3-4 pages of a discussion that will go around while reaching nothing like our last one re Woodward and you love to argue a lot. I'll just say my opinion in one long past again and leave it at this.
He doesn't have a definitive style of play. Anyone who watched enough of their games will know that very well, and they won't point to anything specific in his Madrid team, unlike Pep's team at Barca. His Madrid team usually played on getting it on the flank then cross it. He abused the fact he had the 2 best full backs and Ronaldo. That's not called definitive style, not like Klopp, Sarri or Pep..etc, otherwise Mourinho has definitive style then. I have watches several games in La Liga when I don't know what they were trying to do, and when they looked clueless in one game, they really, really looked like it.
This way is actually not bad per se but you simply need world class players for it to succeed, then you'll just have to give instructions re the game plan, put a good formation with players in their correct positions and make the correct subs without needing to put a certain or a definitive style or coaching the players how to do this or this. Zidane did brilliant in this part and his formations and subs were great. If we put their approach aside, Zidane is cut out of the same clothes as Carlo and Mourinho, they all depend on quality of their players first and foremost when it comes to style. They're not putting a system then get players that play that very specific system. They don't have a certain philosophy to defend in the game. Pep, Sarri and Klopp have that. That doesn't mean they're better/worse than Zidane but these are different categories of managers.
All these aren't bad in general but our team needs someone who's going to put a certain system and persist on building a certain style and coach the players how to attack because we don't have world class players and our players look extremely clueless in certain positions while going on the counter. The movement in the final third is awful. In Madrid he didn't need to tell Ronaldo where to move and Modric where to pass the ball. In United he'll need to do that for several players who lack the basics. We'll look clueless under him in no time just like now under Mourinho and it won't be his problem. It's just that he's not what this group of players need at the moment. If we want a cohesive attacking system like we see at City or Liverpool, Zidane isn't the answer, far from it.
Another thing about rebuilding the team is he himself acknowledged he's not capable of rebuilding the squad and left. He knew it quite well. He knew the team was starting the age and the drop was going to happen sooner or later, in fact it was already happening in his last season. He had enough support from the board and fans and could have stayed as much as he wants and everyone would have given him time to make a rebuild as he's a legend and a lovable figure, but he didn't fancy himself capable of such job. The man's smart. He know his limits as much as his strengths and thus decided when to quit. Looks pointless to discuss if he'll be able to make a rebuild or not when he himself considered himself to not being able to.
Zidane isn't a fluke. He's a very good manager, but not United need right now. He'll be good when we do a good rebuilding process and have a team good enough to start winning, then we can hire him and his in game choices are usually spot on regarding formations and subs. The problem is, the problem with the current United squad is just far, far from putting a good formation, making a good sub or playing a player in his position. The players awfully lack the basics and there's no coherence at all. Zidane isn't going to improve that. That needs someone who is going to take the players to the training ground and start coaching them some proper movement. Currently Jardim is the only free available for that.
That's what I have. Feel free to agree to disagree. Not really in the mood to go any farther today. Maybe another day.