Ilaix and his agent jumped the gun. At least wait to have a real breakthrough season like Pedri did this year, than maybe you have a case (although not really, but let's say for the sake of the argument). He was nowhere near as good, more of a mixed bag in the time he played.
With these cases, judge according to the player. If the player is really special in a kind of obvious way, maybe bend as in to not lose him. If not, stand firm and cut him loose. Is this someone in the same ballpark of like R9 in 1996-97 playing hardball with the next contract after toying with La Liga? Hell no. Nowhere near close to proving himself and gaining leverage.
This is another entry in the paying for "potential" series. Wages or transfers fee the strategy is the same: get yourself a pit bull-like manager to get the clubs paying before the player has to prove himself first. This way, young kids get paid a lot before even making a mark, and then get paid even more since the initial inflated contract becomes the new starting point for "the big one". You pay a lot just for the chance to see if the kid has it or not and then the player and the agent take you to the cleaners. I'm done with that shit since Dembele. Unless we're talking potential like Haaland which is concrete and obvious, and as relevant right now as much as in the future, stand firm.