Also, I feel that Croatia and Morocco play defensive football and that is the strength of both teams and this is the reason they have qualified for the semi final. Argentina and France play an aggressive game and if both these teams reach the final, it will be an epic interesting game to watch.
World cup comes after four years and i really want Argentina and France final (sorry if anyone belongs to Croatia and Morocco & reading this post).
I would rather called it as a counter attack strategy , every coach know when they are facing a team that have a better squad they have to go for counter attack strategy in order to keep the chance of winning the game alive which both morocco and croatia have proven it's work!
I don't see a clear defensive did by morocco , just look at when they go for attacking , super explosive attacking especially by boufal , croatia might a bit more to defensive counter attack since even they struggling to play against japan till the last match against brazil yeah it's a bit obvious.