Despite how they lacked some squad depth, Inter Milan were able to yield to the final of Champions League, what helped them was experience but PSG understood every details. The game was faster than Inter Milan could meet up, watching the game Inter Milan player lacked many attributes that a young talent shouldn't lack while Inter players are already aged and weak. Inter Milan also lost Seria A title to Napoli after occupying the number 1 position, if they don't see any problem with the squad then they are not ready to resurface next season.
I don't understand what Inter lack of, they still use the same squad and same formation, but the results are different. We know Inter's squad are full of old people, but if age was the problem, they won't reach final in Champions League last season.
Maybe it could be other teams already learn how to break Inter's defense? AFAIK Inter have no other strategy.