It might be, we don't know how the Italian system would cope without it. Due to increasing but low test numbers, we don't know how many infected patients there are in Italy. The situation in some hospitals is severe, but it has been for ~2 weeks.
I believe with the number of patients they have, they would've updated the guideline if it wasn't effective at all. But how effective it is we don't know. If a large percentage of some areas is already infected but the health system is still in the state it's in now, it could actually be a good sign. If the current numbers are realistic (which I don't believe at a positive test rate of >30%), it's probably not. We simply cannot know.
I believe with the number of patients they have, they would've updated the guideline if it wasn't effective at all. But how effective it is we don't know. If a large percentage of some areas is already infected but the health system is still in the state it's in now, it could actually be a good sign. If the current numbers are realistic (which I don't believe at a positive test rate of >30%), it's probably not. We simply cannot know.