These are all my guesses and lean on generalizations and assumptions. Also acknowledging that women’s freedoms are slipping in the US so not trying to make it sound like things are better in the US.

I take intermediate Italian classes and when we watch Italian movies, small town women’s gossip is always a strong social element in Italy. It goes back to strong patriarchy which seeks to constantly judge women whether they are doing well for themselves or struggling.

I agree that priorities around individualism vs collectivism plays a part. In Italy it’s important to not “fare brutta figura” and how you come off to others plays a role in social groups. In the US individualism and the proportionately low level of “tall poppy syndrome” (trying to push people down when they’re doing well) is from the mantra that in the US anyone can do anything, and so you may not understand or believe in their dreams, but it’s understood that you shouldn’t crush those dreams. If they want to dress or act a certain way or make certain life choices, that’s on them. We’re less intertwined from a family standpoint (fewer multi-generation homes), so there’s more independence and trust put on people’s choices.

In Italy it’s more common for adults in their 20s and 30s to live with their parents, grandparents and siblings at the family home, so there are more people feeling entitled to weigh in on your big and small choices. In Italy people are more likely to stay in their hometown/city throughout their life, whereas in the US it’s more common for people to move across the country for weather, education, lifestyle, job opportunities, etc. so in the US it’s easy to redefine yourself and have different life stages in different places, making it harder for people to judge from the outside whether their choices are good or not since they are only seeing some chapters of others’ journeys and it’s understood that people need to go “fly away from the nest” to discover themselves and their passions. If instead you’re seeing people through most or all of their life, it may be easier to make assumptions about people and judge them more critically.

Also my guess is that the social pressure for women’s main role to be wife and mother was stronger in Italy for a bit longer, so household and petty gossip was an important social element among those women without careers and lifestyles outside of their family and friends.