I am using the Eurail app and looking at trains from Stresa, Italy to Milan. All of the trips I am seeing in the app are about 2 hours (1:42, 2:31, 2:41, 2:38, 2:41) and many of them involve buses. In fact, the shortest trip is all on bus. I tried several different days and they are all long trips. I have personally taken the train several times as recently as 1 year ago, and know its under 1 hour, maybe even 0:50. Its the same train ride from Domodossola through Stresa down to Milan. 

Is the app having problems, or are the train tracks out of commission? Last year, a track was under construction in France for a few weeks. I don’t know how to find that in Italy.