I personally don't know for sure, how Milan became the more favored team compared to Juventus, whether maybe the factor of playing at home has a big influence on the odds. Because after all, the fact is, so far this season Juventus are still the best team for away games with a very low number of conceded and have good goal productivity for away games compared to other teams.
I can understand that many people favor AC Milan to win the upcoming match because there are 2 main reasons. The first reason is surely about AC Milan more motivation to win at home. When you play at home, you doesn't want to disappoint your home based fans. The second reason is about the available players to play in the match. Juventus has no CF, both of them are injured. This will lower the chance of scoring goals, Juventus has no option for a proper player in the striker position. Meanwhile AC Milan, all of the strikers are ready for the match (
Morata & Tammy Abraham are available).
But perhaps, because Juventus is also still the best team for away games so far this season, making Milan also still get high odds in the @2.xx range like that. Because anyway, if the home team is really favored to win, then the odds are only around @1.xx not @2.xx. Thus, it is still very possible that the match ends in a draw, but I still expect Juventus to be able to top the standings.
When you lost some key players, you will get difficulty to win the match. Moreover, it is the player in the striker position. One of the best midfielders of Juventus (Douglas Luiz) may be not available for the match, too. So, it makes sense if the chance of AC Milan to win the upcoming match is higher than Juventus.