While Inter could technically still catch up to Napoli, they do need to do a lot better for that to happen. Their luck is that Napoli also sucked for a while now, a few weeks, nearly a month I think, which allowed Inter to stay close. If when Inter did terrible, Napoli could have done better, then we would have said that the league is already over.
This is the problem we are facing right now, if we can make this work, then we are certainly seeing things changing and could do a lot better without a doubt. I am sure that we are not going to see things change that much though, we are going to see Inter and Napoli to do pretty much the same for a while longer, win together, draw together, lose together, nothing else.