Doesn't a "no" result maintain the status quo in this case? While populist parties may have been campaigning for "no", is a vote for "keep things as they are" actually a sign of a shift in Italian politics generally?
Short answer: yes and no.
People wanted to say no to Renzi's politics without a clear reason.
The focus shifted from the actual consitituion reform to Renzi's presidency, and he can blame himself.
People felt that Renzi didn't have the right to be the president. People thought that Renzi was a liar, that the constitutional reform was only a way for himself to get more power. So many people voted accordingly to their feelings, not basing their vote on what they tought about the reform.
Italy's vote is the result of an irrational hate directed to the establishment.
People thought they were "saving" the Constitution. Not joking.
In Italy people don't know how many articles are there, when the constitution was written and in which situation it was written. And then they pretend to "save" it.
Sorry for my english. Oh, and that's the opinion from a "yes" voter.
The actual referendum question had only secondary role. It was about changing the constitution to ease bureaucracy, which is traditionally heavy in Italy. But both the PM and the opposition made it also a vote of confidence for the PM
's platform, a gamble which the PM lost.
"No" actually means going back to the 1980s status quo - because the current electoral law has been deemed unconstitutional. That would be some variation of pure proportional, that will make it even harder for the populists to take power, as only Große Koalitions can realistically work.
It would have been in their interest to campaign for Yes, but their mission is to capture the anger of the average voter so they found themselves having to campaign for No to push Renzi out instead.
The constitution will stay the same but status quo will likely change anyway as there will be a new government for the time being and then elections soon. Also, the "No" has been mainly used to end Renzi's government by very different parties (also from the leftist area of the same Democratic Party lead by Renzi), which don't agree on many different issues and won't be able to create a government after the elections.