I agree with you. If Inter Milan lose, they will have to give up hope of winning the title. The other title-seeking teams are improving themselves, and are moving towards winning the title by performing well. Inter Milan is walking on the opposite road. They have lost points against relatively weaker teams in several matches. Inter Milan will also lose to Juventus if their performance does not improve.
this season still leaves a few games, and the concern is how Milan can maintain its consistency to keep winning. A draw will be an opportunity for Napoli to catch up. like Inter and Juve, they must beat each other in the meeting later.
if Milan loses 3 times it will allow Milan to be completely replaced from the temporary throne. but Milan can certainly secure full points in the remaining Serie A matches this season.