Look, Sarri at Lazio dont have Ronaldo, they already score 9 goals. Inter dont have Lukaku they already scores 7 goals
Those names you mentions are a national team players for their respective nation bar De Sciglio (maybe he had in the past). and to be choose as NT player you must compete with around hundred of thousands of player to become the 25 list of name choosen. I don't defend them when they play bad, but maybe they are the man that has a past glory and already lost it. That is a high probability
And the same high probability can applied to managers too

, especially after a long time holiday