This is what's so frustrating. I appreciate the intent behind making it a crime, but unless it happens in the presence of police, and probably only a female officer at that, nothing is going to happen to the men who do it. They'll carry on with impunity.
Honestly, women need to get physical with these men, en masse, so it's safer. See how long they keep catcalling after a group of angry women push them to the the ground and kick them in the balls five or six times.
At least if they report it they'd have to admit to their crime.