Each to his own, I think. If driving for Ferrari was more important for Berger than winning, that's his choice. Some drivers didn't find ultimate success driving for Ferrari, and not for lack of talent; they won titles in other teams: Andretti, Prost, Mansell, Alonso, Vettel. Others refused an offer from Maranello and did OK elsewhere: Moss, Stewart. A few left Ferrari under a cloud: Surtees, Amon, Ickx, Lauda, What I am saying is not a slur on Ferrari, but reality. Ferrari doesn't have the best car all the time, and a driver's career is relatively short. If you have talent, trying to spot the team that may bring you reward is almost as important as driving skills. Fangio won world 5 titles for 4 different makes; he didn't bother with loyalty. You may call that selfish, I call it judicious. I think the age of chivalry is passed.
+1 on this (and your other one on the flexi wings!) It makes no sense for Leclerc to move because quite frankly, he can't move anywhere that's either a move down or a move sideways. He loves Ferrari and is adored by the team and fans...the car is more competitive than expected (though of course not nearly as fast as it should be!), why leave?! Especially with completely new cars coming in...