He's become such a nothing player, it's sad. As recently as 2018 I still hoped he'd become a good defender, obviously not a warrior like Chiello, or elegant passer like (prime) Bonucci, but perhaps a classy intelligent old school CB like Barzagli. In reality though, he just doesn't have anything. Talent, confidence, courage, physique, skill... just nothing there.
Could be a Roma defender by now had he left earlier and developed more as you said, now he's gonna get benched in France once they realize they have 18 year olds in youth team capable of performing just as "well" as Rugani. Good luck to him though, obviously.