Gundogan mostly plays at DM. If Aouar came, he'd be playing mostly at DM. Sometimes at CM. Kinda like Gundo currently does.
Personally, don't think he is necessary. But he is talented. So if there is interest, bring him in. I'm sure Foden will outplay him.
He's so clearly necessary I'm bemused a poster like you doesn't see it.
He instantly brings back the balance to the midfield that our successful seasons were built around. He dictates play, has the intelligent movement between lines and is a threat around the box like Silva, and yet his pressing and speed are far above what David's ever were.
It's obvious to everyone that what happened this season is our midfield broke. Silva couldn't run anymore, Bernardo and Foden can't control a game, so we had to go to the double pivot of Rodri and Gundogan. Which was a mess.
Aouar comes in and fixes it overnight. Job done, midfield fixed. Defence better protected, possession better controlled, attacks in transition quicker.