Of course it would be very interesting if Napoli could be in the Champions League final this season against Manchester City (and even if Manchester City could beat Bayern Munich and also Real Madrid) because I'm also not sure that Chelsea can hold Real Madrid from advancing to the next round because Chelsea's performance this season is not very good and also not on par with other teams who are still in the Champions League now.
Napoli is one of the most desirable teams to reach the final, their chances are very high to be there this season. But let's see how far their journey goes this season because Milan is not always bad to be expected to stop Napoli's run in the Champions League. I might be very surprised if in fact it was Milan who made it to the semi-finals, but if it was Napoli then that would be normal.
I'm not entirely pessimistic about Milan's chances, but Milan seem to have a low chance compared to the other two Serie A teams to the semi-finals. The Napoli vs Manchester City final was great, but we have to see what they get in the quarter-finals first.