Not sure how you can say Pep is ruining either of these players, especially not Sané, who might be the best direct winger in the Premier League already? (I say "direct" because Salah and Hazard are both inverted wingers, or like to play off the shoulder).
But having said that, Jesus is in a critical and confusing stage of his career. He's going to have to decide what type of striker he is, and he's going to have to decide pretty soon. He looks like an expert poacher one week but will then regularly find himself offside or struggle to finish a simple chance. Then there are games where he looks like a brilliant ball-carrier, but he has a tendency to go down easy or just get shrugged off the ball. He has all the attributes to be a genuinely world class player, but he's running out of time to grow into one.
Iheanacho's ceiling was always lower than Jesus', and the fact that Jesus knows Pep's system and plays it well shows that he's maturing into a good striker at the very least, but we've had this before and we need to be wary. When Iheanacho broke out on that US tour in 2014, he had a great first touch and real confidence in possession. Come the winter of 2017, he failed to win a header on the halfway line at Leicester, ten seconds later we were 1-0 down, and Iheanacho never started another game for the club.
I doubt Jesus' case will be that extreme, but what happened to Iheanacho was caused by him never quite pinning down an identity as a striker. He started his City youth career as something of an advanced-#10-cum-striker, but look at the video below and you'll see that his true instincts were to be a poacher. That side of his game improved but his ability to hold onto the ball completely collapsed. Hoping this won't happen to Jesus but there is a chance it might.
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