I don't know where you get such subjective observations from, in my opinion (also subjective) the French team plays very unitedly. Spain, England (and Germany and defending champions Italy) are good teams, but objectively France is doing better and, judging by the individuality of the players, they are also stronger. In my opinion, France looks better both in terms of names and in terms of play.
I can't agree with your observations. French team had all sort of problems when they played during the last Euro Cup. And then the spat went out in public, as the parents of the players were fighting it out in the open. I don't know how much the situation has changed after that, but even during the Qatar edition of the world cup last year, I couldn't find a lot of improvement in team bonding and cohesion. There seems to be a lot of ego issues between the different players, and time and again it comes to the surface in a very ugly way.
These are all subjective arguments, there are just as many scandals, intrigues and other things in small teams, but who cares about them because these are small teams, and all attention is focused on tops like France. For example, the story of Valbuena and Benzema did not prevent France from becoming World Champions and taking silver from the European Championship. Ego, squabbling and competition is normal - we are talking about the top level and without it it is impossible, here the competition is aggravated to the limit in every sense. At the same time, France consistently shows high results despite the loss of any players (Pogba, Benzema, etc.).