The chances do seem easier for AC Milan and several teams not competing in other competitions besides Serie A. However, AC Milan must also have sufficient squad depth for this. To win the Serie A title, every team must be able to perform more consistently in all matches to avoid any rivals blocking their path to the trophy. As we saw last season, Napoli was able to overtake Inter Milan at the top only because Napoli was able to be more consistent in every important match.
Winning Serie A title relies on consistency and this lesson learned from Napoli victory in 2022-2023 season. AC Milan could have edge because they are not competing in as many other tournaments which means less fatigue and fewer games to worry about. This is teaching them to fully focus on their league performance. However this advantage is only useful if they have deep squad. Strong bench lets team rest key players and handle injuries and keep team performance steady throughout season. And if AC Milan has right players to maintain this consistency they will be serious contenders for championship.
Only focusing on the Serie A competition is very profitable and that is from the fitness side of the players and Napoli is proof of last season but for AC Milan next season I doubt it because in terms of overall quality they are not better than other top Serie A teams especially we can see that to cover next season AC Milan did not make many changes so I think for next season AC Milan's performance will not be much different from last season.