This move is a freedom-killing monstrosity and has flavors of Putin-style authoritarianism. The newly-proposed law may be a violation of freedom of expression, being ambiguously broad in its language. There are worries that gatherings or protests of any kind could now be trampled just like this rave ruling.
Remember, this only applies to unlicensed raves with at least 50 partygoers. The left is shocked that a center-right government would implement center-right policies. Italy's government has only begun to honor its pact with its electorate to implement reasonable law and order legislation.