But surely a transport app will make itself available to the whole EU because it wants to be available to tourists. So why does there even need to be a law aro

But surely a transport app will make itself available to the whole EU because it wants to be available to tourists. So why does there even need to be a law around this at all? Presumably apps want to be popular and aren't going to limit themselves to 1 country in the EU. So what is the problem the EU is even trying to solve here? I'm genuinely asking, because not a single example is given. I don't want something theoretical, I'm asking where is a case of someone experiencing actual harm. Because it's very hard to understand this otherwise. Is this actually about apps? Or is it about licensed content like music? Is it anything Apple even has power to change here?