It is indeed a very harsh and a not very thought-out rule. It completely lacks practicality. These are good old classical chants that have existed for a very long time. The FIGC are trying to eradicate these chants with a stupid formal act, which just isn't possible and will only damage the clubs and in turn result in Serie-A becoming a lesser product at times when there are empty stadiums as a consequence. I like that the ultras stand up for their culture and what they believe in. It's not even hatespeech, this, so the chants can definitely be defended. I think this violates people's freedom of speech, and I even believe that the italian authorities should forbid Lega Calcio to impose such rules, in compliance with the European Convention on Human Rights, which Italy has ratified. Italy as a state has a duty to ensure these rights, and if public or private organizations within the country unjustly infringe upon these, then Italy can be held accountable for it in Strasbourg. In my opinion, the Italian state should look into this, and tell the FIGC that it's not acceptable.
I know that the FIGC's intentions are good. Their ultimate goal is to fight racism, which is a good thing. But this isn't the way to go about it.