I disagree with what you said about the 38 matches with compensation. A team can't rule out competition even with a huge number of matches each season. If they think that, then they will never progress.
It may be true at first glance, but if we look further, it is a mistake that should be avoided. It's also worth remembering that they're in the Champions League because of the competition in the domestic league, in this case Serie A. If they think they are compensating for the mistakes they made in the domestic league with a large number of matches it is a mistake they are making,
I agree 100% with what you said. This idea that players can accelerate and decelerate their performance from game to game with a snap of the fingers is bullshit. The best teams are the teams that play with 110% concentration every single game. There is a difference between concentration and intensity. They might reduce intensity when it is possible in order to give their body less of a burden during a game that they are controlling by a large margin, but playing some games on high concentration and some on lower concentration isn't a thing that works. Manchester City is on full steam 99% of the games. AC Milan is a top team that wants to win every single game no matter what the competition is. It is true that there are more prestigious games in the Champions League in terms of the quality of the teams participating, but the players want to win the Serie A with no less desire.
The problem is that when a big club focuses on just one competition it can backfire on them and that's a disadvantage.
Moreover, the Champions League is clearly a gamble because the clubs that are here are all top clubs in every major league. As for domestic competition, even though it is a very long match because there are 38 weeks to go through but on the other hand we must also be aware that if at the beginning they are not too serious, this will make them a little inconvenient especially there could be surprises from other clubs just like Napoli did last season where they could not be overtaken and seemed to be without a fight in Serie A.