I wouldn't say fati had all the power,the club had a two year clause they could have actived if he pulled a moriba & then sell him for big money in the summer.
Negotiations seemed pretty amicable on both sides, and we settled on a fair contract for players who are in his potential bracket, over the course of his contract it works out better than the likes of Rodrygo, who madrid had to pay big money for, he was free.
I only hope the club doesn't go the Messi route with him if he lives up to expectations & offers him a salary increase basically every two years.
This Contract should run until 2 years is left then we start to negotiate again, to avoid the last year contract renewal stress, when he will truly have all the power.