It's because China does nothing. It needs to respond, because Western power only respect strength. China should ban all Italian luxury goods.
1. The Italians are only doing that restrictions for those corporations because they are scared. People who are scared are in no position to really affect change. They too frightened that they could be overwhelmed.
2. Tit-for-tat is not always the answer in a fight. All we need to do is look at the trade war. The reality is that today trade in still increasing to record levels for China, and Chinese American trade is also at record levels. If China went tit-for-tat with the Americans with tariffs, we would not see this outcome. What was the purpose of those Trump tariffs, which are approved by Biden too? I did not know back then, and still do not know today.
3. It is a big whole wide world. Lots of other markets to compete in. If Chinese companies happen to be competing against Italian companies in Africa somewhere, good luck to them, because the gloves are off. A move now, does not mean an immediate counter move is required. This game does not end.
4. The split in Europe over China, that is deepening. The two leading countries, and by a lot, France and Germany most definitely want to maintain and improve relations. Others range from the American vassals sabotaging their own relations with China, and unique cases like Italy who are firmly on the fence.
As far as China is concerned, those few fence sitters can be safely ignored.
Keep upgrading relations with those who want it, keep downgrading relations with those who want it. Why would a European country want to downgrade their relations with China, what will that accomplish and what will they get out of it? That is kind of like asking what was the point of the Trump tariffs? Maybe China losses some business, but among the three biggest economies in Europe are France, Germany, Russia.
To do business, we need trust. If some places in Europe the trust is lacking, then less business will be done, compared to other places where the relationship is on more solid footing.